title: Rationality

text: Rationality is important for solving all kinds of problems in order to efficiently reach one's goal. It is relevant for and discussed in many disciplines. In ethics, one question is whether one can be rational without being moral at the same time. Psychology is interested in how psychological processes implement rationality. This also includes the study of failures to do so, as in the case of cognitive biases. Cognitive and behavioral sciences usually assume that people are rational to predict how they think and act. Logic studies the laws of correct arguments. These laws are highly relevant for the rationality of beliefs. A very influential conception of practical rationality is given in decision theory: it states that a decision is rational if the chosen option has the highest expected utility. Other relevant fields include game theory, Bayesianism, economics, and artificial intelligence.


title: Rationality

text: In its most common sense, rationality is the quality of being guided by reasons or being reasonable. For example, a person who acts rationally has good reasons for what they do. This usually implies that they reflected on the possible consequences of their action and the goal it is supposed to realize. In the case of beliefs, it is rational to believe something if the agent has good evidence for it and it is coherent with the agent's other beliefs. While actions and beliefs are the most paradigmatic forms of rationality, the term is used both in ordinary language and in many academic disciplines to describe a wide variety of things, such as persons, desires, intentions, decisions, policies, and institutions. Because of this variety in different contexts, it has proven difficult to give a unified definition covering all these fields and usages. In this regard, different fields often focus their investigation on one specific conception, type, or aspect of rationality without trying to cover it in its most general sense.


title: Rationality

text: These different forms of rationality are sometimes divided into abilities, processes, mental states, and persons. For example, when it is claimed that humans are rational animals, this usually refers to the ability to think and act in reasonable ways. It does not imply that all humans are rational all the time: this ability is exercised in some cases but not in others. On the other hand, the term can also refer to the process of reasoning that results from exercising this ability. Often many additional activities of the higher cognitive faculties are included as well, such as acquiring concepts, judging, deliberating, planning, and deciding as well as the formation of desires and intentions. These processes usually affect some kind of change in the thinker's mental states. In this regard, one can also talk of the rationality of mental states, like beliefs and intentions. A person who possesses these forms of rationality to a sufficiently high degree may themselves be called "rational". In some cases, also non-mental results of rational processes may qualify as rational. For example, the arrangement of products in a supermarket can be rational if it is based on a rational plan.


title: Rationality

text: The term "rational" has two opposites: "irrational" and "arational". Arational things are outside the domain of rational evaluation, like digestive processes or the weather. Things within the domain of rationality are either rational or irrational depending on whether they fulfill the standards of rationality. For example, beliefs, actions, or general policies are rational if there is a good reason for them and irrational otherwise. It is not clear in all cases what belongs to the domain of rational assessment. For example, there are disagreements about whether desires and emotions can be evaluated as rational and irrational rather than arational. The term "irrational" is sometimes used in a wide sense to include cases of arationality.


title: Rationality

text: The meaning of the terms "rational" and "irrational" in academic discourse often differs from how they are used in everyday language. Examples of behaviors considered irrational in ordinary discourse are giving into temptations, going out late even though one has to get up early in the morning, smoking despite being aware of the health risks, or believing in astrology. In the academic discourse, on the other hand, rationality is usually identified with being guided by reasons or following norms of internal coherence. Some of the earlier examples may qualify as rational in the academic sense depending on the circumstances. Examples of irrationality in this sense include cognitive biases, making arithmetic mistakes, and violating the laws of probability theory when assessing the likelihood of future events. This article focuses mainly on irrationality in the academic sense.


title: Rationality

text: The terms "rationality", "reason", and "reasoning" are frequently used as synonyms. But in technical contexts, their meanings are often distinguished. Reason is usually understood as the faculty responsible for the process of reasoning. This process aims at improving mental states. Reasoning tries to ensure that the norms of rationality obtain. It differs from rationality nonetheless since other psychological processes besides reasoning may have the same effect. Rationality derives etymologically from the Latin term "".


title: Rationality

text: There are many disputes about the essential characteristics of rationality. It is often understood in relational terms: something, like a belief or an intention, is rational because of how it is related to something else. But there are disagreements as to what it has to be related to and in what way. For reason-based accounts, the relation to a reason that justifies or explains the rational state is central. For coherence-based accounts, the relation of coherence between mental states matters. There is a lively discussion in the contemporary literature on whether reason-based accounts or coherence-based accounts are superior. Some theorists also try to understand rationality in relation to the goals it tries to realize.


title: Rationality

text: Other disputes in this field concern whether rationality depends only on the agent's mind or also on external factors, whether rationality requires a review of all one's beliefs from scratch, and whether we should always be rational.


title: Rationality

text: A common idea of many theories of rationality is that it can be defined in terms of reasons. On this view, to be rational means to respond correctly to reasons. For example, the fact that a food is healthy is a reason to eat it. So this reason makes it rational for the agent to eat the food. An important aspect of this interpretation is that it is not sufficient to merely act accidentally in accordance with reasons. Instead, "responding" to reasons implies that one acts intentionally because of these reasons.


title: Rationality

text: Some theorists understand reasons as external facts. This view has been criticized based on the claim that, in order to respond to reasons, people have to be aware of them, i.e. if have some form of epistemic access. But lacking this access is not automatically irrational. In one example by John Broome, the agent eats a fish contaminated with salmonella, which is a strong reason against eating the fish. But since the agent could not have known this fact, eating the fish is rational for them. Because of such problems, many theorists have opted for an internalist version of this account. This means that the agent does not need to respond to reasons in general, but only to reasons they have or possess. The success of such approaches depends a lot on what it means to have a reason and there are various disagreements on this issue. A common approach is to hold that this access is given through the possession of evidence in the form of cognitive mental states, like perceptions and knowledge. A similar version states that "rationality consists in responding correctly to beliefs about reasons". So it is rational to bring an umbrella if the agent has strong evidence that it is going to rain. But without this evidence, it would be rational to leave the umbrella at home, even if, unbeknownst to the agent, it is going to rain. These versions avoid the previous objection since rationality no longer requires the agent to respond to external factors of which they could not have been aware.


title: Rationality

text: A problem faced by all forms of reason-responsiveness theories is that there are usually many reasons relevant and some of them may conflict with each other. So while salmonella contamination is a reason against eating the fish, its good taste and the desire not to offend the host are reasons in favor of eating it. This problem is usually approached by weighing all the different reasons. This way, one does not respond directly to each reason individually but instead to their weighted sum. Cases of conflict are thus solved since one side usually outweighs the other. So despite the reasons cited in favor of eating the fish, the balance of reasons stands against it, since avoiding a salmonella infection is a much weightier reason than the other reasons cited. This can be expressed by stating that rational agents pick the option favored by the balance of reasons.


title: Rationality

text: However, other objections to the reason-responsiveness account are not so easily solved. They often focus on cases where reasons require the agent to be irrational, leading to a rational dilemma. For example, if terrorists threaten to blow up a city unless the agent forms an irrational belief, this is a very weighty reason to do all in one's power to violate the norms of rationality.


title: Rationality

text: An influential rival to the reason-responsiveness account understands rationality as internal coherence. On this view, a person is rational to the extent that their mental states and actions are coherent with each other. Diverse versions of this approach exist that differ in how they understand coherence and what rules of coherence they propose. A general distinction in this regard is between negative and positive coherence. Negative coherence is an uncontroversial aspect of most such theories: it requires the absence of contradictions and inconsistencies. This means that the agent's mental states do not clash with each other. In some cases, inconsistencies are rather obvious, as when a person believes that it will rain tomorrow and that it will not rain tomorrow. In complex cases, inconsistencies may be difficult to detect, for example, when a person believes in the axioms of Euclidean geometry and is nonetheless convinced that it is possible to square the circle. Positive coherence refers to the support that different mental states provide for each other. For example, there is positive coherence between the belief that there are eight planets in the solar system and the belief that there are less than ten planets in the solar system: the earlier belief implies the latter belief. Other types of support through positive coherence include explanatory and causal connections.


title: Rationality

text: Coherence-based accounts are also referred to as rule-based accounts since the different aspects of coherence are often expressed in precise rules. In this regard, to be rational means to follow the rules of rationality in thought and action. According to the enkratic rule, for example, rational agents are required to intend what they believe they ought to do. This requires coherence between beliefs and intentions. The norm of persistence states that agents should retain their intentions over time. This way, earlier mental states cohere with later ones. It is also possible to distinguish different types of rationality, such as theoretical or practical rationality, based on the different sets of rules they require.


title: Rationality

text: One problem with such coherence-based accounts of rationality is that the norms can enter into conflict with each other, so-called rational dilemmas. For example, if the agent has a pre-existing intention that turns out to conflict with their beliefs, then the enkratic norm requires them to change it, which is disallowed by the norm of persistence. This suggests that, in cases of rational dilemmas, it is impossible to be rational, no matter which norm is privileged. Some defenders of coherence theories of rationality have argued that, when formulated correctly, the norms of rationality cannot enter into conflict with each other. That means that rational dilemmas are impossible. This is sometimes tied to additional non-trivial assumptions, such that ethical dilemmas also do not exist. A different response is to bite the bullet and allow that rational dilemmas exist. This has the consequence that, in such cases, rationality is not possible for the agent and theories of rationality cannot offer guidance to them. These problems are avoided by reason-responsiveness accounts of rationality since they "allow for rationality despite conflicting reasons but [coherence-based accounts] do not allow for rationality despite conflicting requirements". Some theorists suggest a weaker criterion of coherence to avoid cases of necessary irrationality: rationality requires not to obey all norms of coherence but to obey as many norms as possible. So in rational dilemmas, agents can still be rational if they violate the minimal number of rational requirements.


title: Rationality

text: Another criticism rests on the claim that coherence-based accounts are either redundant or false. On this view, either the rules recommend the same option as the balance of reasons or a different option. If they recommend the same option, they are redundant. If they recommend a different option, they are false since, according to its critics, there is no special value in sticking to rules against the balance of reasons.


title: Rationality

text: A different approach characterizes rationality in relation to the goals it aims to achieve. In this regard, theoretical rationality aims at epistemic goals, like acquiring truth and avoiding falsehood. Practical rationality, on the other hand, aims at non-epistemic goals, like moral, prudential, political, economic, or aesthetic goals. This is usually understood in the sense that rationality follows these goals but does not set them. So rationality may be understood as a "minister without portfolio" since it serves goals external to itself. This issue has been the source of an important historical discussion between David Hume and Immanuel Kant. The slogan of Hume's position is that "reason is the slave of the passions". This is often understood as the claim that rationality concerns only how to reach a goal but not whether the goal should be pursued at all. So people with perverse or weird goals may still be perfectly rational. This position is opposed by Kant, who argues that rationality requires having the right goals and motives.


title: Rationality

text: According to William Frankena there are four conceptions of rationality based on the goals it tries to achieve. They correspond to egoism, utilitarianism, perfectionism, and intuitionism. According to the egoist perspective, rationality implies looking out for one's own happiness. This contrasts with the utilitarian point of view, which states that rationality entails trying to contribute to everyone's well-being or to the greatest general good. For perfectionism, a certain ideal of perfection, either moral or non-moral, is the goal of rationality. According to the intuitionist perspective, something is rational "if and only if [it] conforms to self-evident truths, intuited by reason". These different perspectives diverge a lot concerning the behavior they prescribe. One problem for all of them is that they ignore the role of the evidence or information possessed by the agent. In this regard, it matters for rationality not just whether the agent acts efficiently towards a certain goal but also what information they have and how their actions appear reasonable from this perspective. Richard Brandt responds to this idea by proposing a conception of rationality based on relevant information: "Rationality is a matter of what would survive scrutiny by all relevant information." This implies that the subject repeatedly reflects on all the relevant facts, including formal facts like the laws of logic.


title: Rationality

text: An important contemporary discussion in the field of rationality is between internalists and externalists. Both sides agree that rationality demands and depends in some sense on reasons. They disagree on what reasons are relevant or how to conceive those reasons. Internalists understand reasons as mental states, for example, as perceptions, beliefs, or desires. On this view, an action may be rational because it is in tune with the agent's beliefs and realizes their desires. Externalists, on the other hand, see reasons as external factors about what is good or right. They state that whether an action is rational also depends on its actual consequences. The difference between the two positions is that internalists affirm and externalists reject the claim that rationality supervenes on the mind. This claim means that it only depends on the person's mind whether they are rational and not on external factors. So for internalism, two persons with the same mental states would both have the same degree of rationality independent of how different their external situation is. Because of this limitation, rationality can diverge from actuality. So if the agent has a lot of misleading evidence, it may be rational for them to turn left even though the actually correct path goes right.


title: Rationality

text: Bernard Williams has criticized externalist conceptions of rationality based on the claim that rationality should help explain what motivates the agent to act. This is easy for internalism but difficult for externalism since external reasons can be independent of the agent's motivation. Externalists have responded to this objection by distinguishing between motivational and normative reasons. Motivational reasons explain why someone acts the way they do while normative reasons explain why someone ought to act in a certain way. Ideally, the two overlap, but they can come apart. For example, liking chocolate cake is a motivational reason for eating it while having high blood pressure is a normative reason for not eating it. The problem of rationality is primarily concerned with normative reasons. This is especially true for various contemporary philosophers who hold that rationality can be reduced to normative reasons. The distinction between motivational and normative reasons is usually accepted, but many theorists have raised doubts that rationality can be identified with normativity. On this view, rationality may sometimes recommend suboptimal actions, for example, because the agent lacks important information or has false information. In this regard, discussions between internalism and externalism overlap with discussions of the normativity of rationality.


title: Rationality

text: An important implication of internalist conceptions is that rationality is relative to the person's perspective or mental states. Whether a belief or an action is rational usually depends on which mental states the person has. So carrying an umbrella for the walk to the supermarket is rational for a person believing that it will rain but irrational for another person who lacks this belief. According to Robert Audi, this can be explained in terms of experience: what is rational depends on the agent's experience. Since different people make different experiences, there are differences in what is rational for them.


title: Rationality

text: Rationality is normative in the sense that it sets up certain rules or standards of correctness: to be rational is to comply with certain requirements. For example, rationality requires that the agent does not have contradictory beliefs. Many discussions on this issue concern the question of what exactly these standards are. Some theorists characterize the normativity of rationality in the deontological terms of obligations and permissions. Others understand them from an evaluative perspective as good or valuable. A further approach is to talk of rationality based on what is praise- and blameworthy. It is important to distinguish the norms of rationality from other types of norms. For example, some forms of fashion prescribe that men do not wear bell-bottom trousers. Understood in the strongest sense, a norm prescribes what an agent ought to do or what they have most reason to do. The norms of fashion are not norms in this strong sense: that it is unfashionable does not mean that men ought not to wear bell-bottom trousers.


title: Rationality

text: Most discussions of the normativity of rationality are interested in the strong sense, i.e. whether agents ought always to be rational. This is sometimes termed a substantive account of rationality in contrast to structural accounts. One important argument in favor of the normativity of rationality is based on considerations of praise- and blameworthiness. It states that we usually hold each other responsible for being rational and criticize each other when we fail to do so. This practice indicates that irrationality is some form of fault on the side of the subject that should not be the case. A strong counterexample to this position is due to John Broome, who considers the case of a fish an agent wants to eat. It contains salmonella, which is a decisive reason why the agent ought not to eat it. But the agent is unaware of this fact, which is why it is rational for them to eat the fish. So this would be a case where normativity and rationality come apart. This example can be generalized in the sense that rationality only depends on the reasons accessible to the agent or how things appear to them. What one ought to do, on the other hand, is determined by objectively existing reasons. In the ideal case, rationality and normativity may coincide but they come apart either if the agent lacks access to a reason or if he has a mistaken belief about the presence of a reason. These considerations are summed up in the statement that rationality supervenes only on the agent's mind but normativity does not.


title: Rationality

text: But there are also thought experiments in favor of the normativity of rationality. One, due to Frank Jackson, involves a doctor who receives a patient with a mild condition and has to prescribe one out of three drugs: drug A resulting in a partial cure, drug B resulting in a complete cure, or drug C resulting in the patient's death. The doctor's problem is that they cannot tell which of the drugs B and C results in a complete cure and which one in the patient's death. The objectively best case would be for the patient to get drug B, but it would be highly irresponsible for the doctor to prescribe it given the uncertainty about its effects. So the doctor ought to prescribe the less effective drug A, which is also the rational choice. This thought experiment indicates that rationality and normativity coincide since what is rational and what one ought to do depends on the agent's mind after all.


title: Rationality

text: Some theorists have responded to these thought experiments by distinguishing between normativity and responsibility. On this view, critique of irrational behavior, like the doctor prescribing drug B, involves a negative evaluation of the agent in terms of responsibility but remains silent on normative issues. On a competence-based account, which defines rationality in terms of the competence of responding to reasons, such behavior can be understood as a failure to execute one's competence. But sometimes we are lucky and we succeed in the normative dimension despite failing to perform competently, i.e. rationally, due to being irresponsible. The opposite can also be the case: bad luck may result in failure despite a responsible, competent performance. This explains how rationality and normativity can come apart despite our practice of criticizing irrationality.


title: Rationality

text: The concept of normativity can also be used to distinguish different theories of rationality. Normative theories explore the normative nature of rationality. They are concerned with rules and ideals that govern how the mind should work. Descriptive theories, on the other hand, investigate how the mind actually works. This includes issues like under which circumstances the ideal rules are followed as well as studying the underlying psychological processes responsible for rational thought. Descriptive theories are often investigated in empirical psychology while philosophy tends to focus more on normative issues. This division also reflects how different these two types are investigated.


title: Rationality

text: Descriptive and normative theorists usually employ different methodologies in their research. Descriptive issues are studied by empirical research. This can take the form of studies that present their participants with a cognitive problem. It is then observed how the participants solve the problem, possibly together with explanations of why they arrived at a specific solution. Normative issues, on the other hand, are usually investigated in similar ways to how the formal sciences conduct their inquiry. In the field of theoretical rationality, for example, it is accepted that deductive reasoning in the form of modus ponens leads to rational beliefs. This claim can be investigated using methods like rational intuition or careful deliberation toward a reflective equilibrium. These forms of investigation can arrive at conclusions about what forms of thought are rational and irrational without depending on empirical evidence.


title: Rationality

text: An important question in this field concerns the relation between descriptive and normative approaches to rationality. One difficulty in this regard is that there is in many cases a huge gap between what the norms of ideal rationality prescribe and how people actually reason. Examples of normative systems of rationality are classical logic, probability theory, and decision theory. Actual reasoners often diverge from these standards because of cognitive biases, heuristics, or other mental limitations.


title: Rationality

text: Traditionally, it was often assumed that actual human reasoning should follow the rules described in normative theories. On this view, any discrepancy is a form of irrationality that should be avoided. However, this usually ignores the human limitations of the mind. Given these limitations, various discrepancies may be necessary (and in this sense "rational") to get the most useful results. For example, the ideal rational norms of decision theory demand that the agent should always choose the option with the highest expected value. However, calculating the expected value of each option may take a very long time in complex situations and may not be worth the trouble. This is reflected in the fact that actual reasoners often settle for an option that is good enough without making certain that it is really the best option available. A further difficulty in this regard is Hume's law, which states that one cannot deduce what ought to be based on what is. So just because a certain heuristic or cognitive bias is present in a specific case, it should not be inferred that it should be present. One approach to these problems is to hold that descriptive and normative theories talk about different types of rationality. This way, there is no contradiction between the two and both can be correct in their own field. Similar problems are discussed in so-called naturalized epistemology.


title: Rationality

text: Rationality is usually understood as conservative in the sense that rational agents do not start from zero but already possess many beliefs and intentions. Reasoning takes place on the background of these pre-existing mental states and tries to improve them. This way, the original beliefs and intentions are privileged: one keeps them unless a reason to doubt them is encountered. Some forms of epistemic foundationalism reject this approach. According to them, the whole system of beliefs is to be justified by self-evident beliefs. Examples of such self-evident beliefs may include immediate experiences as well as simple logical and mathematical axioms.


title: Rationality

text: An important difference between conservatism and foundationalism concerns their differing conceptions of the burden of proof. According to conservativism, the burden of proof is always in favor of already established belief: in the absence of new evidence, it is rational to keep the mental states one already has. According to foundationalism, the burden of proof is always in favor of suspending mental states. For example, the agent reflects on their pre-existing belief that the Taj Mahal is in Agra but is unable to access any reason for or against this belief. In this case, conservatists think it is rational to keep this belief while foundationalists reject it as irrational due to the lack of reasons. In this regard, conservatism is much closer to the ordinary conception of rationality. One problem for foundationalism is that very few beliefs, if any, would remain if this approach was carried out meticulously. Another is that enormous mental resources would be required to constantly keep track of all the justificatory relations connecting non-fundamental beliefs to fundamental ones.


title: Rationality

text: Rationality is discussed in a great variety of fields, often in very different terms. While some theorists try to provide a unifying conception expressing the features shared by all forms of rationality, the more common approach is to articulate the different aspects of the individual forms of rationality. The most common distinction is between theoretical and practical rationality. Other classifications include categories for ideal and bounded rationality as well as for individual and social rationality.


title: Rationality

text: The most influential distinction contrasts theoretical or epistemic rationality with practical rationality. Its theoretical side concerns the rationality of beliefs: whether it is rational to hold a given belief and how certain one should be about it. Practical rationality, on the other hand, is about the rationality of actions, intentions, and decisions. This corresponds to the distinction between theoretical reasoning and practical reasoning: theoretical reasoning tries to assess whether the agent should change their beliefs while practical reasoning tries to assess whether the agent should change their plans and intentions.


title: Rationality

text: Theoretical rationality concerns the rationality of cognitive mental states, in particular, of beliefs. It is common to distinguish between two factors. The first factor is about the fact that good reasons are necessary for a belief to be rational. This is usually understood in terms of evidence provided by the so-called sources of knowledge, i.e. faculties like perception, introspection, and memory. In this regard, it is often argued that to be rational, the believer has to respond to the impressions or reasons presented by these sources. For example, the visual impression of the sunlight on a tree makes it rational to believe that the sun is shining. In this regard, it may also be relevant whether the formed belief is involuntary and implicit


title: Rationality

text: The second factor pertains to the norms and procedures of rationality that govern how agents should form beliefs based on this evidence. These norms include the rules of inference discussed in regular logic as well as other norms of coherence between mental states. In the case of rules of inference, the premises of a valid argument offer support to the conclusion and make therefore the belief in the conclusion rational. The support offered by the premises can either be deductive or non-deductive. In both cases, believing in the premises of an argument makes it rational to also believe in its conclusion. The difference between the two is given by how the premises support the conclusion. For deductive reasoning, the premises offer the strongest possible support: it is impossible for the conclusion to be false if the premises are true. The premises of non-deductive arguments also offer support for their conclusion. But this support is not absolute: the truth of the premises does not guarantee the truth of the conclusion. Instead, the premises make it more likely that the conclusion is true. In this case, it is usually demanded that the non-deductive support is sufficiently strong if the belief in the conclusion is to be rational.


title: Rationality

text: An important form of theoretical irrationality is motivationally biased belief, sometimes referred to as wishful thinking. In this case, beliefs are formed based on one's desires or what is pleasing to imagine without proper evidential support. Faulty reasoning in the form of formal and informal fallacies is another cause of theoretical irrationality.


title: Rationality

text: All forms of practical rationality are concerned with how we act. It pertains both to actions directly as well as to mental states and events preceding actions, like intentions and decisions. There are various aspects of practical rationality, such as how to pick a goal to follow and how to choose the means for reaching this goal. Other issues include the coherence between different intentions as well as between beliefs and intentions.


title: Rationality

text: Some theorists define the rationality of actions in terms of beliefs and desires. On this view, an action to bring about a certain goal is rational if the agent has the desire to bring about this goal and the belief that their action will realize it. A stronger version of this view requires that the responsible beliefs and desires are rational themselves. A very influential conception of the rationality of decisions comes from decision theory. In decisions, the agent is presented with a set of possible courses of action and has to choose one among them. Decision theory holds that the agent should choose the alternative that has the highest expected value. Practical rationality includes the field of actions but not of behavior in general. The difference between the two is that actions are intentional behavior, i.e. they are performed for a purpose and guided by it. In this regard, intentional behavior like driving a car is either rational or irrational while non-intentional behavior like sneezing is outside the domain of rationality.


title: Rationality

text: For various other practical phenomena, there is no clear consensus on whether they belong to this domain or not. For example, concerning the rationality of desires, two important theories are proceduralism and substantivism. According to proceduralism, there is an important distinction between instrumental and noninstrumental desires. A desire is instrumental if its fulfillment serves as a means to the fulfillment of another desire. For example, Jack is sick and wants to take medicine to get healthy again. In this case, the desire to take the medicine is instrumental since it only serves as a means to Jack's noninstrumental desire to get healthy. Both proceduralism and substantivism usually agree that a person can be irrational if they lack an instrumental desire despite having the corresponding noninstrumental desire and being aware that it acts as a means. Proceduralists hold that this is the only way a desire can be irrational. Substantivists, on the other hand, allow that noninstrumental desires may also be irrational. In this regard, a substantivist could claim that it would be irrational for Jack to lack his noninstrumental desire to be healthy. Similar debates focus on the rationality of emotions.


title: Rationality

text: Theoretical and practical rationality are often discussed separately and there are many differences between them. In some cases, they even conflict with each other. However, there are also various ways in which they overlap and depend on each other.


title: Rationality

text: It is sometimes claimed that theoretical rationality aims at truth while practical rationality aims at goodness. According to John Searle, the difference can be expressed in terms of "direction of fit". On this view, theoretical rationality is about how the mind corresponds to the world by representing it. Practical rationality, on the other hand, is about how the world corresponds to the ideal set up by the mind and how it should be changed. Another difference is that arbitrary choices are sometimes needed for practical rationality. For example, there may be two equally good routes available to reach a goal. On the practical level, one has to choose one of them if one wants to reach the goal. It would even be practically irrational to resist this arbitrary choice, as exemplified by Buridan's ass. But on the theoretical level, one does not have to form a belief about which route was taken upon hearing that someone reached the goal. In this case, the arbitrary choice for one belief rather than the other would be theoretically irrational. Instead, the agent should suspend their belief either way if they lack sufficient reasons. Another difference is that practical rationality is guided by specific goals and desires, in contrast to theoretical rationality. So it is practically rational to take medicine if one has the desire to cure a sickness. But it is theoretically irrational to adopt the belief that one is healthy just because one desires this. This is a form of wishful thinking.


title: Rationality

text: In some cases, the demands of practical and theoretical rationality conflict with each other. For example, the practical reason of loyalty to one's child may demand the belief that they are innocent while the evidence linking them to the crime may demand a belief in their guilt on the theoretical level.


title: Rationality

text: But the two domains also overlap in certain ways. For example, the norm of rationality known as enkrasia links beliefs and intentions. It states that "[r]ationality requires of you that you intend to F if you believe your reasons require you to F". Failing to fulfill this requirement results in cases of irrationality known as akrasia or weakness of the will. Another form of overlap is that the study of the rules governing practical rationality is a theoretical matter. And practical considerations may determine whether to pursue theoretical rationality on a certain issue as well as how much time and resources to invest in the inquiry. It is often held that practical rationality presupposes theoretical rationality. This is based on the idea that to decide what should be done, one needs to know what is the case. But one can assess what is the case independently of knowing what should be done. So in this regard, one can study theoretical rationality as a distinct discipline independent of practical rationality but not the other way round. However, this independence is rejected by some forms of doxastic voluntarism. They hold that theoretical rationality can be understood as one type of practical rationality. This is based on the controversial claim that we can decide what to believe. It can take the form of "epistemic decision theory", which states that people try to fulfill epistemic aims when deciding what to believe. A similar idea is defended by Jesús Mosterín. He argues that the proper object of rationality is not "belief" but "acceptance". He understands acceptance as a voluntary and context-dependent decision to affirm a proposition.


title: Rationality

text: Various theories of rationality assume some form of ideal rationality, for example, by demanding that rational agents obey all the laws and implications of logic. This can include the requirement that if the agent believes a proposition, they should also believe in everything that logically follows from this proposition. However, many theorists reject this form of logical omniscience as a requirement for rationality. They argue that, since the human mind is limited, rationality has to be defined accordingly to account for how actual finite humans possess some form of resource-limited rationality.


title: Rationality

text: According to the position of bounded rationality, theories of rationality should take into account cognitive limitations, such as incomplete knowledge, imperfect memory, and limited capacities of computation and representation. An important research question in this field is about how cognitive agents use heuristics rather than brute calculations to solve problems and make decisions. According to the satisficing heuristic, for example, agents usually stop their search for the best option once an option is found that meets their desired achievement level. In this regard, people often do not continue to search for the best possible option, even though this is what theories of ideal rationality commonly demand. Using heuristics can be highly rational as a way to adapt to the limitations of the human mind, especially in complex cases where these limitations make brute calculations impossible or very time- and resource-intensive.


title: Rationality

text: Most discussions and research in the academic literature focus on individual rationality. This concerns the rationality of individual persons, for example, whether their beliefs and actions are rational. But the question of rationality can also be applied to groups as a whole on the social level. This form of social or collective rationality concerns both theoretical and practical issues like group beliefs and group decisions. And just like in the individual case, it is possible to study these phenomena as well as the processes and structures that are responsible for them. On the social level, there are various forms of cooperation to reach a shared goal. In the theoretical cases, a group of jurors may first discuss and then vote to determine whether the defendant is guilty. Or in the practical case, politicians may cooperate to implement new regulations to combat climate change. These forms of cooperation can be judged on their social rationality depending on how they are implemented and on the quality of the results they bear. Some theorists try to reduce social rationality to individual rationality by holding that the group processes are rational to the extent that the individuals participating in them are rational. But such a reduction is frequently rejected.


title: Rationality

text: Various studies indicate that group rationality often outperforms individual rationality. For example, groups of people working together on the Wason selection task usually perform better than individuals by themselves. This form of group superiority is sometimes termed "wisdom of crowds" and may be explained based on the claim that competent individuals have a stronger impact on the group decision than others. However, this is not always the case and sometimes groups perform worse due to conformity or unwillingness to bring up controversial issues.


title: Rationality

text: Many other classifications are discussed in the academic literature. One important distinction is between approaches to rationality based on the output or on the process. Process-oriented theories of rationality are common in cognitive psychology and study how cognitive systems process inputs to generate outputs. Output-oriented approaches are more common in philosophy and investigate the rationality of the resulting states. Another distinction is between relative and categorical judgments of rationality. In the relative case, rationality is judged based on limited information or evidence while categorical judgments take all the evidence into account and are thus judgments "all things considered". For example, believing that one's investments will multiply can be rational in a relative sense because it is based on one's astrological horoscope. But this belief is irrational in a categorical sense if the belief in astrology is itself irrational.


title: Rationality

text: Rationality is central to solving many problems, both on the local and the global scale. This is often based on the idea that rationality is necessary to act efficiently and to reach all kinds of goals. This includes goals from diverse fields, such as ethical goals, humanist goals, scientific goals, and even religious goals. The study of rationality is very old and has occupied many of the greatest minds since ancient Greek. This interest is often motivated by discovering the potentials and limitations of our minds. Various theorists even see rationality as the essence of being human, often in an attempt to distinguish humans from other animals. However, this strong affirmation has been subjected to many criticisms, for example, that humans are not rational all the time and that non-human animals also show diverse forms of intelligence.


title: Rationality

text: The topic of rationality is relevant to a variety of disciplines. It plays a central role in philosophy, psychology, Bayesianism, decision theory, and game theory. But it is also covered in other disciplines, such as artificial intelligence, behavioral economics, microeconomics, and neuroscience. Some forms of research restrict themselves to one specific domain while others investigate the topic in an interdisciplinary manner by drawing insights from different fields.


title: Rationality

text: The term "paradox of rationality" has a variety of meanings. It is often used for puzzles or unsolved problems of rationality. Some are just situations where it is not clear what the rational person should do. Others involve apparent faults within rationality itself, for example, where rationality seems to recommend a suboptimal course of action. A special case are so-called rational dilemmas, in which it is impossible to be rational since two norms of rationality conflict with each other. Examples of paradoxes of rationality include Pascal's Wager, the Prisoner's dilemma, Buridan's ass, and the St. Petersburg paradox.


title: Rationality

text: The German scholar Max Weber proposed an interpretation of social action that distinguished between four different idealized types of rationality.


title: Rationality

text: The first, which he called "Zweckrational" or purposive/instrumental rationality, is related to the expectations about the behavior of other human beings or objects in the environment. These expectations serve as means for a particular actor to attain ends, ends which Weber noted were "rationally pursued and calculated." The second type, Weber called "Wertrational" or value/belief-oriented. Here the action is undertaken for what one might call reasons intrinsic to the actor: some ethical, aesthetic, religious or other motives, independent of whether it will lead to success. The third type was affectual, determined by an actor's specific affect, feeling, or emotion—to which Weber himself said that this was a kind of rationality that was on the borderline of what he considered "meaningfully oriented." The fourth was traditional or conventional, determined by ingrained habituation. Weber emphasized that it was very unusual to find only one of these orientations: combinations were the norm. His usage also makes clear that he considered the first two as more significant than the others, and it is arguable that the third and fourth are subtypes of the first two.


title: Rationality

text: The advantage in Weber's interpretation of rationality is that it avoids a value-laden assessment, say, that certain kinds of beliefs are irrational. Instead, Weber suggests that ground or motive can be given—for religious or affect reasons, for example—that may meet the criterion of explanation or justification even if it is not an explanation that fits the "Zweckrational" orientation of means and ends. The opposite is therefore also true: some means-ends explanations will not satisfy those whose grounds for action are "Wertrational".


title: Rationality

text: Weber's constructions of rationality have been critiqued both from a Habermasian (1984) perspective (as devoid of social context and under-theorised in terms of social power) and also from a feminist perspective (Eagleton, 2003) whereby Weber's rationality constructs are viewed as imbued with masculine values and oriented toward the maintenance of male power. An alternative position on rationality (which includes both bounded rationality, as well as the affective and value-based arguments of Weber) can be found in the critique of Etzioni (1988), who reframes thought on decision-making to argue for a reversal of the position put forward by Weber. Etzioni illustrates how purposive/instrumental reasoning is subordinated by normative considerations (ideas on how people 'ought' to behave) and affective considerations (as a support system for the development of human relationships).


title: Rationality

text: Richard Brandt proposed a "reforming definition" of rationality, arguing someone is rational if their notions survive a form of cognitive-psychotherapy.


title: Rationality

text: Robert Audi developed a comprehensive account of rationality that covers both the theoretical and the practical side of rationality. This account centers on the notion of a "ground": a mental state is rational if it is "well-grounded" in a source of justification. Irrational mental states, on the other hand, lack a sufficient ground. For example, the perceptual experience of a tree when looking outside the window can ground the rationality of the belief that there is a tree outside.


title: Rationality

text: Audi is committed to a form of foundationalism: the idea that justified beliefs, or in his case, rational states in general, can be divided into two groups: the "foundation" and the "superstructure". The mental states in the superstructure receive their justification from other rational mental states while the foundational mental states receive their justification from a more basic source. For example, the above-mentioned belief that there is a tree outside is foundational since it is based on a basic source: perception. Knowing that trees grow in soil, we may deduce that there is soil outside. This belief is equally rational, being supported by an adequate ground, but it belongs to the superstructure since its rationality is grounded in the rationality of another belief. Desires, like beliefs, form a hierarchy: intrinsic desires are at the foundation while instrumental desires belong to the superstructure. In order to link the instrumental desire to the intrinsic desire an extra element is needed: a belief that the fulfillment of the instrumental desire is a means to the fulfillment of the intrinsic desire.


title: Rationality

text: Audi asserts that all the basic sources providing justification for the foundational mental states come from experience. As for "beliefs", there are four types of experience that act as sources: perception, memory, introspection, and rational intuition. The main basic source of the rationality of "desires", on the other hand, comes in the form of hedonic experience: the experience of pleasure and pain. So, for example, a desire to eat ice-cream is rational if it is based on experiences in which the agent enjoyed the taste of ice-cream, and irrational if it lacks such a support. Because of its dependence on experience, rationality can be defined as a kind of responsiveness to experience.


title: Rationality

text: "Actions", in contrast to beliefs and desires, do not have a source of justification of their own. Their rationality is grounded in the rationality of other states instead: in the rationality of beliefs and desires. Desires motivate actions. Beliefs are needed here, as in the case of instrumental desires, to bridge a gap and link two elements. Audi distinguishes the "focal" rationality of individual mental states from the "global" rationality of "persons". Global rationality has a derivative status: it depends on the focal rationality. Or more precisely: "Global rationality is reached when a person has a sufficiently integrated system of sufficiently well-grounded propositional attitudes, emotions, and actions". Rationality is "relative" in the sense that it depends on the experience of the person in question. Since different people undergo different experiences, what is rational to believe for one person may be irrational to believe for another person. That a belief is rational does not entail that it is "true".


title: Rationality

text: The problem of rationality is relevant to various issues in ethics and morality. Many debates center around the question of whether rationality implies morality or is possible without it. Some examples based on common sense suggest that the two can come apart. For example, some immoral psychopaths are highly intelligent in the pursuit of their schemes and may, therefore, be seen as rational. However, there are also considerations suggesting that the two are closely related to each other. For example, according to the principle of universality, "one's reasons for acting are acceptable only if it is acceptable that everyone acts on such reasons". A similar formulation is given in Immanuel Kant's categorical imperative: "act only according to that maxim whereby you can, at the same time, will that it should become a universal law". The principle of universality has been suggested as a basic principle both for morality and for rationality. This is closely related to the question of whether agents have a duty to be rational. Another issue concerns the value of rationality. In this regard, it is often held that human lives are more important than animal lives because humans are rational.


title: Rationality

text: Many psychological theories have been proposed to describe how reasoning happens and what underlying psychological processes are responsible. One of their goals is to explain how the different types of irrationality happen and why some types are more prevalent than others. They include "mental logic theories", "mental model theories", and "dual process theories". An important psychological area of study focuses on cognitive biases. Cognitive biases are systematic tendencies to engage in erroneous or irrational forms of thinking, judging, and acting. Examples include the confirmation bias, the self-serving bias, the hindsight bias, and the Dunning–Kruger effect. Some empirical findings suggest that metacognition is an important aspect of rationality. The idea behind this claim is that reasoning is carried out more efficiently and reliably if the responsible thought processes are properly controlled and monitored.


title: Rationality

text: The Wason selection task is an influential test for studying rationality and reasoning abilities. In it, four cards are placed before the participants. Each has a number on one side and a letter on the opposite side. In one case, the visible sides of the four cards are A, D, 4, and 7. The participant is then asked which cards need to be turned around in order to verify the conditional claim "if there is a vowel on one side of the card, then there is an even number on the other side of the card". The correct answer is A and 7. But this answer is only given by about 10%. Many choose card 4 instead even though there is no requirement on what letters may appear on its opposite side. An important insight from using these and similar tests is that the rational ability of the participants is usually significantly better for concrete and realistic cases than for abstract or implausible cases. Various contemporary studies in this field use Bayesian probability theory to study subjective degrees of belief, for example, how the believer's certainty in the premises is carried over to the conclusion through reasoning.


title: Rationality

text: In the psychology of reasoning, psychologists and cognitive scientists have defended different positions on human rationality. One prominent view, due to Philip Johnson-Laird and Ruth M. J. Byrne among others is that humans are rational in principle but they err in practice, that is, humans have the competence to be rational but their performance is limited by various factors. However, it has been argued that many standard tests of reasoning, such as those on the conjunction fallacy, on the Wason selection task, or the base rate fallacy suffer from methodological and conceptual problems. This has led to disputes in psychology over whether researchers should (only) use standard rules of logic, probability theory and statistics, or rational choice theory as norms of good reasoning. Opponents of this view, such as Gerd Gigerenzer, favor a conception of bounded rationality, especially for tasks under high uncertainty. The concept of rationality continues to be debated by psychologists, economists and cognitive scientists.


title: Rationality

text: The psychologist Jean Piaget gave an influential account of how the stages in human development from childhood to adulthood can be understood in terms of the increase of rational and logical abilities. He identifies four stages associated with rough age groups: the sensorimotor stage below the age of two, the preoperational state until the age of seven, the concrete operational stage until the age of eleven, and the formal operational stage afterward. Rational or logical reasoning only takes place in the last stage and is related to abstract thinking, concept formation, reasoning, planning, and problem-solving.


title: Rationality

text: According to A. C. Grayling, rationality "must be independent of emotions, personal feelings or any kind of instincts". Certain findings in cognitive science and neuroscience show that no human has ever satisfied this criterion, except perhaps a person with no affective feelings, for example, an individual with a massively damaged amygdala or severe psychopathy. Thus, such an idealized form of rationality is best exemplified by computers, and not people. However, scholars may productively appeal to the idealization as a point of reference. In his book, "The Edge of Reason: A Rational Skeptic in an Irrational World," British philosopher Julian Baggini sets out to debunk myths about reason (e.g., that it is "purely objective and requires no subjective judgment").


title: Rationality

text: Cognitive and behavioral sciences try to describe, explain, and predict how people think and act. Their models are often based on the assumption that people are rational. For example, classical economics is based on the assumption that people are rational agents that maximize expected utility. However, people often depart from the ideal standards of rationality in various ways. For example, they may only look for confirming evidence and ignore disconfirming evidence. Another factor studied in this regard are the limitations of human intellectual capacities. Many discrepancies from rationality are caused by limited time, memory, or attention. Often heuristics and rules of thumb are used to mitigate these limitations, but they may lead to new forms of irrationality.


title: Rationality

text: Theoretical rationality is closely related to logic, but not identical to it. Logic is often defined as the study of correct arguments. This concerns the relation between the propositions used in the argument: whether its premises offer support to its conclusion. Theoretical rationality, on the other hand, is about what to believe or how to change one's beliefs. The laws of logic are relevant to rationality since the agent should change their beliefs if they violate these laws. But logic is not directly about what to believe. Additionally, there are also other factors and norms besides logic that determine whether it is rational to hold or change a belief. The study of rationality in logic is more concerned with epistemic rationality, that is, attaining beliefs in a rational manner, than instrumental rationality.


title: Rationality

text: An influential account of practical rationality is given by decision theory. Decisions are situations where a number of possible courses of action are available to the agent, who has to choose one of them. Decision theory investigates the rules governing which action should be chosen. It assumes that each action may lead to a variety of outcomes. Each outcome is associated with a conditional probability and a utility. The "expected gain" of an outcome can be calculated by multiplying its conditional probability with its utility. the "expected utility" of an act is equivalent to the sum of all expected gains of the outcomes associated with it. From these basic ingredients, it is possible to define the rationality of decisions: a decision is rational if it selects the act with the highest expected utility. While decision theory gives a very precise formal treatment of this issue, it leaves open the empirical problem of how to assign utilities and probabilities. So decision theory can still lead to bad empirical decisions if it is based on poor assignments.


title: Rationality

text: According to decision theorists, rationality is primarily a matter of internal consistency. This means that a person's mental states like beliefs and preferences are consistent with each other or do not go against each other. One consequence of this position is that people with obviously false beliefs or perverse preferences may still count as rational if these mental states are consistent with their other mental states. Utility is often understood in terms of self-interest or personal preferences. However, this is not a necessary aspect of decisions theory and it can also be interpreted in terms of goodness or value in general.


title: Rationality

text: Game theory is closely related to decision theory and the problem of rational choice. Rational choice is based on the idea that rational agents perform a cost-benefit analysis of all available options and choose the option that is most beneficial from their point of view. In the case of game theory, several agents are involved. This further complicates the situation since whether a given option is the best choice for one agent may depend on choices made by other agents. Game theory can be used to analyze various situations, like playing chess, firms competing for business, or animals fighting over prey. Rationality is a core assumption of game theory: it is assumed that each player chooses rationally based on what is most beneficial from their point of view. This way, the agent may be able to anticipate how others choose and what their best choice is relative to the behavior of the others. This often results in a Nash equilibrium, which constitutes a set of strategies, one for each player, where no player can improve their outcome by unilaterally changing their strategy.


title: Rationality

text: A popular contemporary approach to rationality is based on Bayesian epistemology. Bayesian epistemology sees belief as a continuous phenomenon that comes in degrees. For example, Daniel is relatively sure that the Boston Celtics will win their next match and absolutely certain that two plus two equals four. In this case, the degree of the first belief is weaker than the degree of the second belief. These degrees are usually referred to as "credences" and represented by numbers between 0 and 1. 0 corresponds to full disbelief, 1 corresponds to full belief and 0.5 corresponds to suspension of belief. Bayesians understand this in terms of probability: the higher the credence, the higher the subjective probability that the believed proposition is true. As probabilities, they are subject to the laws of probability theory. These laws act as norms of rationality: beliefs are rational if they comply with them and irrational if they violate them. For example, it would be irrational to have a credence of 0.9 that it will rain tomorrow together with another credence of 0.9 that it will not rain tomorrow. This account of rationality can also be extended to the practical domain by requiring that agents maximize their subjective expected utility. This way, Bayesianism can provide a unified account of both theoretical and practical rationality.


title: Rationality

text: Rationality plays a key role in economics and there are several strands to this. Firstly, there is the concept of instrumentality—basically the idea that people and organisations are instrumentally rational—that is, adopt the best actions to achieve their goals. Secondly, there is an axiomatic concept that rationality is a matter of being logically consistent within your preferences and beliefs. Thirdly, people have focused on the accuracy of beliefs and full use of information—in this view, a person who is not rational has beliefs that do not fully use the information they have.


title: Rationality

text: Debates within economic sociology also arise as to whether or not people or organizations are "really" rational, as well as whether it makes sense to model them as such in formal models. Some have argued that a kind of bounded rationality makes more sense for such models.


title: Rationality

text: Others think that any kind of rationality along the lines of rational choice theory is a useless concept for understanding human behavior; the term "homo economicus" (economic man: the imaginary man being assumed in economic models who is logically consistent but amoral) was coined largely in honor of this view. Behavioral economics aims to account for economic actors as they actually are, allowing for psychological biases, rather than assuming idealized instrumental rationality.


title: Rationality

text: The field of artificial intelligence is concerned, among other things, with how problems of rationality can be implemented and solved by computers. Within artificial intelligence, a "rational agent" is typically one that maximizes its expected utility, given its current knowledge. Utility is the usefulness of the consequences of its actions. The utility function is arbitrarily defined by the designer, but should be a function of "performance", which is the directly measurable consequences, such as winning or losing money. In order to make a safe agent that plays defensively, a nonlinear function of performance is often desired, so that the reward for winning is lower than the punishment for losing. An agent might be rational within its own problem area, but finding the rational decision for arbitrarily complex problems is not practically possible. The rationality of human thought is a key problem in the psychology of reasoning.


title: Rationality

text: There is an ongoing debate over the merits of using “rationality” in the study of international relations (IR). Some scholars hold it indispensable. Others are more critical. Still, the pervasive and persistent usage of "rationality" in political science and IR is beyond dispute. "Rationality" remains ubiquitous in this field. Abulof finds that Some 40% of all scholarly references to "foreign policy" allude to "rationality"—and this ratio goes up to more than half of pertinent academic publications in the 2000s. He further argues that when it comes to concrete security and foreign policies, IR employment of rationality borders on "malpractice": rationality-based descriptions are largely either false or unfalsifiable; many observers fail to explicate the meaning of "rationality" they employ; and the concept is frequently used politically to distinguish between "us and them."


title: Crystal healing

text: Crystal healing is a pseudoscientific alternative-medicine practice that uses semiprecious stones and crystals such as quartz, agate, amethyst or opal. Adherents of the practice claim that these have healing powers, but there is no scientific basis for this claim. Practitioners of crystal healing believe they can boost low energy, prevent bad energy, release blocked energy, and transform a body's aura.


title: Crystal healing

text: In one method, the practitioner places crystals on different parts of the body, often corresponding to chakras; or else the practitioner places crystals around the body in an attempt to construct an "energy grid", which is purported to surround the client with healing energy. Scientific investigations have found no evidence that such "energy grids" actually exist, and there is no evidence that crystal healing has any greater effect upon the body than any other placebo.


title: Crystal healing

text: Where the practice is popular, it fosters commercial demand for crystals, which can result in environmental damage and exploitative child labor to mine the crystals.


title: Crystal healing

text: In Plato's account of Atlantis, crystal healing is also mentioned. According to Plato, the Atlanteans used crystals to read minds and transmit thoughts. The first historical documentation of crystals originated from the Ancient Sumerians (c. 4500 to c. 2000BC). The Sumerians used crystals in their magical formulas.


title: Crystal healing

text: Ancient Egyptians mined for crystals and used them to make jewelry. Crystals or gemstones were also used in practice, for their metaphysical properties. Specifically, they used crystals as aids for health and protection. They often would bury a lapis lazuli scarab with their deceased, with the belief that it would protect them in the afterlife. Additionally, in Ancient Egypt amulets were used to ensure the well-being of the individual. The amulet's shape, decoration, inscription, color, material, or ritual performed with the amulet dictated its power. Amulets were worn or placed on the body, in the form of stones, piercings, rings, necklaces, or other jewelry. The Egyptians used amulets to benefit their afterlife, often representing an Egyptian deity and their specific powers. Amulets were also placed on mummies or in between the mummy's bandages, with funerary pieces usually being larger than those worn by the living. In funeral practices they also used headrest amulets, these were full-size headrests placed in tombs to protect the dead, they also symbolized the deceased rising and being revived, and the sun rising between two hills, which symbolized resurrection and rebirth.


title: Crystal healing

text: The Ancient Greeks assigned a multitude of properties to crystals. The word 'crystal' is derived from the Greek word "krýstallos" which translates to "ice". The Ancient Greeks believed that clear quartz crystals were a water that had frozen to the point where it would remain in its solid form. The word "amethyst" in Ancient Greek language means "not intoxicate." Amethyst was worn as an amulet that they believed would aid hangovers or prevent intoxication.


title: Crystal healing

text: Precious stones have been thought of as objects that can aid in healing—in a practice known as lapidary medicine—by a variety of cultures. The Hopi Native Americans of Arizona use quartz crystals to assist in diagnosing illnesses. Both Pliny the Elder and Galen claimed that certain crystals had medicinal properties. In Europe, the belief in the healing powers of crystals (and in particular crystal amulets) persisted into the Middle Ages. The alleged medicinal properties of precious stones, as well as other powers they were believed to hold, were collected in texts known as lapidaries, which remained popular in Medieval and Early Modern Europe until the 17th century.


title: Crystal healing

text: Across cultures, different stones can symbolize or provide aide for different things. An example of this is rose quartz. In Egypt, it was believed rose quartz could prevent aging, but the Romans used rose quartz as a seal to signify ownership, while in the Middle Ages it was used in healing potions, today rose quartz is known as the "love stone" and is used to balance emotions, and heal anger and disappointment.


title: Crystal healing

text: In the English speaking world, crystal healing is heavily associated with the New Age spiritual movement: "the middle-class New Age healing activity "par excellence"". In contrast with other forms of complementary and alternative medicine (CAM), participants in crystal healing view the practice as "individuated", that is "dependent on extreme personalization and creative expression." Practitioners of crystal healing purport that certain physical properties such as shape, color, and markings, determine the ailments that a stone can heal; lists of such links are published in commonly distributed texts. Paradoxically, practitioners also "hold the view that crystals have no intrinsic qualities but that, instead, their quality changes according to both" participants. After selecting the stones by color or their believed metaphysical qualities, they place them on parts of the body. Color selection and placement of stones are done according to concepts of grounding, "chakras", or energy grids.


title: Crystal healing

text: Worldwide, retail sales of crystals were estimated to amount to more than US$1 billion per year in 2019.


title: Crystal healing

text: India, China, Brazil, and Madagascar are the main producers of crystals. In Madagascar, one of the sources of crystals, most crystals are mined in unsafe, non-industrial or "homemade" mines, with parents and children working together to dig crystals from pits and tunnels they dig with shovels. The miners are usually paid between 17 and 23 cents per kilogram for rose quartz (less than a penny per ounce). The miner's income may be just 0.1% of the final retail price. Some people in the industry say that the low pay for miners is because customers in developed countries want low retail prices; others say that it is due to shops in developed countries wanting to be more profitable.


title: Crystal healing

text: There is no peer-reviewed scientific evidence that crystal healing has any effect; it is considered a pseudoscience. Alleged successes of crystal healing can be attributed to the placebo effect. Furthermore, there is no scientific basis for the concepts of "chakras", being "blocked", energy grids requiring grounding, or other such terms; they are widely understood to be nothing more than terms used by adherents to lend credibility to their practices. Energy, as a scientific term, is a very well-defined concept that is readily measurable and bears little resemblance to the esoteric concept of energy used by proponents of crystal healing.


title: Crystal healing

text: In 1999, researchers French and Williams conducted a study to investigate the power of crystals compared with a placebo. Eighty volunteers were asked to meditate with either a quartz crystal, or a placebo stone which was indistinguishable from quartz. Many of the participants reported feeling typical "crystal effects"; however, this was irrespective of whether the crystals were real or placebo. In 2001 Christopher French, head of the anomalistic psychology research unit at the University of London and colleagues from Goldsmiths College outlined their study of crystal healing at the British Psychological Society Centenary Annual Conference, concluding: "There is no evidence that crystal healing works over and above a placebo effect."


title: Crystal healing

text: Crystal healing effects could also be attributed to cognitive bias (which occurs when the believers want the practice to be true and see only things that back up that desire).


title: Crystal healing

text: Crystal healing techniques are also practiced on animals, although some veterinary organizations, such as the British Veterinary Association, have warned that these methods are not scientifically proven and state that people should seek the advice of a vet before using alternative techniques.


title: Crystal healing

text: Crystal healing proponents and 5G conspiracy theorists have falsely alleged the pseudoscientific and misinformational belief that shungite may absorb 5G radiation.


title: Fee-fi-fo-fum

text: "Fee-fi-fo-fum" is the first line of a historical quatrain (or sometimes couplet) famous for its use in the classic English fairy tale "Jack and the Beanstalk". The poem, as given in Joseph Jacobs' 1890 rendition, is as follows:


title: Fee-fi-fo-fum

text: Though the rhyme is tetrametric, it follows no consistent metrical foot; however, the lines correspond roughly to a monosyllabic tetrameter, a dactylic tetrameter, a trochaic tetrameter, and an iambic tetrameter respectively. The poem has historically made use of assonant half rhyme.


title: Fee-fi-fo-fum

text: The rhyme appears in the 1596 pamphlet "Haue with You to Saffron-Walden" written by Thomas Nashe, who mentions that the rhyme was already old and its origins obscure:


title: Fee-fi-fo-fum

text: In William Shakespeare's play "King Lear" (c. 1605), in Act III, Scene IV, the character Edgar referring to the legend of Childe Rowland exclaims:


title: Fee-fi-fo-fum

text: The verse in "King Lear" makes use of the archaic word "fie", used to express disapproval. This word is used repeatedly in Shakespeare's works: King Lear shouts, "Fie, fie, fie! pah, pah!", and in "Antony and Cleopatra", Mark Antony exclaims, "O fie, fie, fie!"


title: Fee-fi-fo-fum

text: The earliest known printed version of the Jack the Giant-Killer tale appears in "The history of Jack and the Giants" (Newcastle, 1711) and this, and later versions (found in chapbooks), include renditions of the poem, recited by the giant Thunderdell:


title: Fee-fi-fo-fum

text: Charles Mackay proposes in "The Gaelic Etymology of the Languages of Western Europe" that the seemingly meaningless string of syllables "Fa fe fi fo fum" is actually a coherent phrase of ancient Gaelic, and that the complete quatrain covertly expresses the Celts' cultural detestation of the invading Angles and Saxons:


title: Hard to Kill

text: Hard to Kill is a 1990 American action thriller film directed by Bruce Malmuth, starring Steven Seagal, Kelly LeBrock, William Sadler and Frederick Coffin. Seagal's second film after "Above the Law", it features him as Mason Storm, a detective who falls into a coma after being shot during a fire-fight that killed his wife. Reawakening seven years later, Storm embarks on a journey to avenge the death of his wife, and expose the corruption of Senator Vernon Trent. The film was released on February 9, 1990, and grossed $59 million.


title: Hard to Kill

text: In 1983, Mason Storm (Steven Seagal), a Los Angeles police detective investigates a mob meeting that takes place by a pier. He records a shadowy figure who assures the mob they can rely on his political support. Mason is spotted, but escapes. Unaware that he is monitored by corrupt cops, Mason informs his partner, Becker and his friend Lt. O’Malley that he has evidence of corruption.


title: Hard to Kill

text: Mason hides the videotape in his house. When he goes upstairs, a hit squad composed of corrupt policemen, including Jack Axel and Max Quentero, break in and proceed to murder Mason's wife and shoot him. Mason's young son, Sonny, escapes out of a window. The corrupt policemen frame Mason, making it look like a murder-suicide. At the same time, assassins kill Mason's partner. Later at the hospital, Mason is first pronounced dead, but is then discovered to be alive, although in a coma. To prevent the assassins from finishing the job, Lieutenant O'Malley tells the medics to keep Mason's status a secret.


title: Hard to Kill

text: Seven years later, Mason wakes from his coma. Andy Stewart (Kelly LeBrock), one of his nurses, makes a phone call, which is intercepted by corrupt police officers. They send Axel to finish the job and kill the nurses to whom Mason might have talked. Mason realizes that he is still in danger, but his muscles have atrophied to where he can barely move. He manages to get to an elevator, and when Andy sees her co-workers killed, she helps Mason escape.


title: Hard to Kill

text: Needing time to recuperate, Andy takes Mason to a friend's house, where Mason uses his knowledge of acupuncture, moxibustion and other meditation techniques to recover his strength. While training, Mason hears a commercial for Senator Vernon Trent and recognizes the voice from the pier. Mason contacts O'Malley, who supplies him with weapons and tells him that his son is still alive. O'Malley adopted Sonny and sent him to a private school so that he would be out of danger. He arranges to meet O'Malley and his now-teenage son, Sonny, at a train station later. After O'Malley leaves, Senator Trent's men find the house and attempt to kill Andy and Mason, but they both manage to escape.


title: Hard to Kill

text: Posing as a real estate agent, Mason recovers the hidden videotape from his old house. O'Malley and Sonny arrive at the train station, but are confronted by some of the Senator's men. Sonny is able to run away with the tape, but O'Malley is killed. When Mason arrives, he sees Sonny running away from Quentero and Nolan. Mason catches up with the men, subdues Nolan by breaking his leg and throwing him in a trash bin. He then reaches Quentero before Sonny is grabbed, and the two fight one another. Mason beats up Quentero and recognizes him as one of the men who took part in the assault on Mason's home and the murder of his wife. Mason then proceeds to snap Quentero's neck, killing him and saving his son. Mason then goes after Senator Trent.


title: Hard to Kill

text: At the Senator's mansion, Mason sneaks in and manages to eliminate the Senator's men one by one. Mason fights with Axel in the billiard room and avenges Felicia by jamming a piece of a pool cue into Axel's neck, killing him. Next, Mason leaves a death taunt to Capt. Hulland, another corrupt cop who betrayed Mason to Trent, and stalks Hulland through the house before cornering the corrupt captain near the fireplace. Mason then strangles Hulland with his necktie and breaks his neck, killing him. Mason finally confronts Senator Trent and holds him at gunpoint when the police storm the mansion. However, they reveal that they had already seen the film and knew that Mason was set up. Trent is arrested, and Mason is reunited with Andy and his son and walks off as the image from the videotape is played on the news, showing Trent coming out of the shadows briefly.


title: Hard to Kill

text: Originally, the movie ended with Mason actually killing Trent, and some time later Mason, Andy and Sonny attending a funeral for O'Malley. The theatrical trailer shows parts of the original ending.


title: Hard to Kill

text: "Hard to Kill" debuted at number 1 at the U.S. box office with an opening weekend gross of $9.2 million, the biggest 3-day February opening at the time. It eventually grossed $47.4 million in the United States and Canada and $59 million total box office worldwide


title: Hard to Kill

text: It holds a 33% approval rating on Rotten Tomatoes based on 15 reviews; the average rating is 4.1/10. Audiences polled by CinemaScore gave the film an average grade of "A−" on an A+ to F scale.


title: Hard to Kill

text: Owen Gleiberman of "Entertainment Weekly" rated it a letter grade of D− and called Seagal as generic an actor as the film. In describing the film as "a lively one for its genre", Janet Maslin of "The New York Times" wrote, "Mr. Seagal is effective for both his novelty value and his ability to be both literally and figuratively disarming."


title: Westermarck effect

text: The Westermarck effect, also known as reverse sexual imprinting, is a psychological hypothesis that people tend not to be attracted to peers with whom they lived like siblings before age six. This hypothesis was first proposed by Finnish anthropologist Edvard Westermarck in his book "The History of Human Marriage" (1891) as one explanation for the incest taboo.


title: Westermarck effect

text: The Westermarck effect has achieved some empirical support. Proponents point to evidence from the Israeli kibbutz system, from the Chinese Shim-pua marriage customs, and from biologically-related families.


title: Westermarck effect

text: In the case of the Israeli kibbutzim (collective farms), children were reared somewhat communally in peer groups, based on age, not biological relations. A study of the marriage patterns of these children later in life revealed that out of the nearly 3,000 marriages that occurred across the kibbutz system, only 14 were between children from the same peer group. Of those 14, none had been reared together during the first six years of life. This result suggests that the Westermarck effect operates during the period from birth to the age of six.


title: Westermarck effect

text: In Shim-pua marriages, a girl would be adopted into a family as the future wife of a son, often an infant at that time. These marriages often failed, as would be expected according to the Westermarck hypothesis.


title: Westermarck effect

text: Studies show that cousin-marriage in Lebanon has a lower success rate if the cousins were raised in sibling-like conditions, first-cousin unions being more successful in Pakistan if there was a substantial age difference, as well as reduced marital appeal for cousins who grew up sleeping in the same room in Morocco. Evidence also indicates that siblings separated for extended periods of time since childhood were more likely to report having engaged in sexual activity with one another.


title: Westermarck effect

text: Eran Shor and Dalit Simchai revisited the kibbutzim results and found sexual attraction where it hadn't been acted on. They conclude that any innate aversion needs to be backed up by social pressures and norms.


title: G8

text: The Group of Eight (G8) was an inter-governmental political forum from 1997 until 2014. It had formed from incorporating Russia into the Group of Seven, or G7, and returned to its previous name after Russia left in 2014.


title: G8

text: The forum originated with a 1975 summit hosted by France that brought together representatives of six governments: France, Germany, Italy, Japan, the United Kingdom, and the United States, thus leading to the name Group of Six or G6. The summit came to be known as the Group of Seven in 1976 with the addition of Canada. Russia was added to the political forum from 1997, which the following year became known as the G8. In March 2014 Russia was suspended indefinitely following the annexation of Crimea, whereupon the political forum name reverted to G7. In January 2017, Russia announced its permanent withdrawal from the G8. However, several representatives of G7 countries stated that they would be interested in Russia's return to the group. The European Union (or predecessor institutions) was represented at the G8 since the 1980s as a "nonenumerated" participant, but originally could not host or chair summits. The 40th summit was the first time the European Union was able to host and chair a summit. Collectively, in 2012 the G8 nations comprised 50.1 percent of 2012 global nominal GDP and 40.9 percent of global GDP (PPP). The G8 countries were not strictly the largest in the world nor the highest-income per capita, but they do represent the largest high-income countries.


title: G8

text: "G7" can refer to the member states in aggregate or to the annual summit meeting of the G7 heads of government. G7 ministers also meet throughout the year, such as the G7 finance ministers (who meet four times a year), G7 foreign ministers, or G7 environment ministers.


title: G8

text: Each calendar year, the responsibility of hosting the G8 was rotated through the member states in the following order: France, United States, United Kingdom, Russia (suspended), Germany, Japan, Italy, and Canada. The holder of the presidency sets the agenda, hosts the summit for that year, and determines which ministerial meetings will take place.


title: G8

text: In 2005, the UK government initiated the practice of inviting five leading emerging markets – Brazil, China, India, Mexico, and South Africa – to participate in the G8 meetings that came to be known as G8+5. With the G20 major economies growing in stature since the 2008 Washington summit, world leaders from the group announced at their Pittsburgh summit in September 2009 that the group would replace the G8 as the main economic council of wealthy nations. Nevertheless, the G7 retains its relevance as a "steering group for the West", with special significance appointed to Japan.


title: G8

text: Following 1994's G7 summit in Naples, Russian officials held separate meetings with leaders of the G7 after the group's summits. This informal arrangement was dubbed the Political 8 (P8)—or, colloquially, the G7+1. At the invitation of UK Prime Minister Tony Blair and U.S. President Bill Clinton, President Boris Yeltsin was invited first as a guest observer, later as a full participant. It was seen as a way to encourage Yeltsin with his capitalist reforms. Russia formally joined the group in 1998, resulting in the Group of Eight, or G8.


title: G8

text: Major focus of the G8 since 2009 has been the global supply of food. At the 2009 L'Aquila summit, the G8's members promised to contribute $22 billion to the issue. By 2015, 93% of funds had been disbursed to projects like sustainable agriculture development and adequate emergency food aid assistance.


title: G8

text: At the 2012 summit, President Barack Obama asked G8 leaders to adopt the New Alliance for Food Security and Nutrition initiative to "help the rural poor produce more food and sell it in thriving local and regional markets as well as on the global market". Ghana became one of the first six African countries to sign up to the G8 New Alliance for Food Security and Nutrition in 2012. There was, however, almost no knowledge of the G8 initiative among some stakeholders, including farmers, academics and agricultural campaign groups. Confusion surrounding the plans was made worse, critics say, by "a dizzying array of regional and national agriculture programmes that are inaccessible to ordinary people."


title: G8

text: On 24 March 2014, the G7 members cancelled the planned G8 summit that was to be held in June of that year in the Russian city of Sochi, and suspended Russia's membership of the group, due to Russia's annexation of Crimea; nevertheless, they stopped short of outright permanent expulsion. Russian foreign minister Sergei Lavrov downplayed the importance of the decision by the U.S. and its allies, and pointed out that major international decisions were made by the G20 countries.


title: G8

text: Later on, the Italian Foreign Affairs minister Federica Mogherini and other Italian authorities, along with the EastWest Institute board member Wolfgang Ischinger, suggested that Russia may restore its membership in the group. In April 2015, the German foreign minister Frank-Walter Steinmeier said that Russia would be welcomed to return to G8 provided the Minsk Protocol was implemented. In 2016, he added that "none of the major international conflicts can be solved without Russia", and the G7 countries will consider Russia's return to the group in 2017. The same year, Japanese Prime Minister Shinzō Abe called for Russia's return to G8, stating that Russia's involvement is "crucial to tackling multiple crises in the Middle East". In January 2017, the Italian foreign minister Angelino Alfano said that Italy hopes for "resuming the G8 format with Russia and ending the atmosphere of the Cold War". On 13 January 2017, Russia announced that it would permanently leave the G8 grouping. Nonetheless, Christian Lindner, the leader of Free Democratic Party of Germany and member of the Bundestag, said that Putin should be "asked to join the table of the G7" so that one could "talk with him and not about him", and "we cannot make all things dependent on the situation in Crimea". In April 2018, the German politicians and members of the Bundestag Sahra Wagenknecht and Alexander Graf Lambsdorff said that Russia should be invited back to the group and attend the 2018 summit in Canada: "Russia should again be at the table during the [June] summit at the latest" because "peace in Europe and also in the Middle East is only possible with Russia". The US President Donald Trump also stated that Russia should be reinstated to the group; his appeal was supported by the Italian Prime Minister Giuseppe Conte. After several G7 members quickly rejected US President Trump suggestion to accept again Russian Federation in the G8, Russian Foreign Minister Lavrov said the Russian Federation wasn't interested in rejoining the political forum. He also said that G20 is sufficient for Russian Federation. In the final statement of the 2018 meeting in Canada, the G7 members announced to continue sanctions and also to be ready to take further restrictive measures against the Russian Federation for the failure of Minsk Agreement complete implementation.


title: G8

text: By design, the G8 deliberately lacked an administrative structure like those for international organizations, such as the United Nations or the World Bank. The group does not have a permanent secretariat, or offices for its members.


title: G8

text: The presidency of the group rotates annually among member countries, with each new term beginning on 1 January of the year. The rotation order is: France, the United States, the United Kingdom, Russia (suspended), Germany, Japan, Italy, and Canada. The country holding the presidency is responsible for planning and hosting a series of ministerial-level meetings, leading up to a mid-year summit attended by the heads of government. The president of the European Commission participates as an equal in all summit events.


title: G8

text: The ministerial meetings bring together ministers responsible for various portfolios to discuss issues of mutual or global concern. The range of topics include health, law enforcement, labor, economic and social development, energy, environment, foreign affairs, justice and interior, terrorism, and trade. There are also a separate set of meetings known as the G8+5, created during the 2005 Gleneagles, Scotland summit, that is attended by finance and energy ministers from all eight member countries in addition to the five "outreach countries" which are also known as the Group of Five—Brazil, People's Republic of China, India, Mexico, and South Africa.


title: G8

text: In June 2005, justice ministers and interior ministers from the G8 countries agreed to launch an international database on pedophiles. The G8 officials also agreed to pool data on terrorism, subject to restrictions by privacy and security laws in individual countries.


title: G8

text: At the Heiligendamm Summit in 2007, the G8 acknowledged a proposal from the EU for a worldwide initiative on efficient energy use. They agreed to explore, along with the International Energy Agency, the most effective means to promote energy efficiency internationally. A year later, on 8 June 2008, the G8 along with China, India, South Korea and the European Community established the International Partnership for Energy Efficiency Cooperation, at the Energy Ministerial meeting hosted by Japan holding 2008 G8 Presidency, in Aomori.


title: G8

text: G8 Finance Ministers, whilst in preparation for the 34th Summit of the G8 Heads of State and Government in Toyako, Hokkaido, met on the 13 and 14 June 2008, in Osaka, Japan. They agreed to the "G8 Action Plan for Climate Change to Enhance the Engagement of Private and Public Financial Institutions." In closing, Ministers supported the launch of new Climate Investment Funds (CIFs) by the World Bank, which will help existing efforts until a new framework under the UNFCCC is implemented after 2012. The UNFCCC is not on track to meeting any of its stated goals.


title: G8

text: In July 2005, the G8 Summit endorsed the IPHE in its Plan of Action on Climate Change, Clean Energy and Sustainable Development, and identified it as a medium of cooperation and collaboration to develop clean energy technologies.


title: G8

text: The first G8 summit was held in 1997 after Russia formally joined the G7 group, and the last one was held in 2013. The 2014 summit was scheduled to be held in Russia. However, due to the Crimean crisis, the other seven countries decided to hold a separate meeting without Russia as a G7 summit in Brussels, Belgium.


title: G8

text: One type of criticism is that members of G8 do not do enough to help global problems, due to strict patent policy and other issues related to globalization. In "Unraveling Global Apartheid", political analyst Titus Alexander described the G7, as it was in 1996, as the 'cabinet' of global minority rule, with a coordinating role in world affairs.


title: G8

text: In 2012 The Heritage Foundation criticized the G8 for advocating food security without making room for economic freedom.


title: G8

text: The G8's relevance has been subject to debate from 2008 onward. It represented the major industrialized countries but critics argued that the G8 no longer represented the world's most powerful economies, as China has surpassed every economy but the United States.


title: G8

text: Vladimir Putin did not attend the 2012 G8 summit at Camp David, causing "Foreign Policy" magazine to remark that the summit has generally outlived its usefulness as a viable international gathering of foreign leaders. Two years later, Russia was suspended from the G8, then chose to leave permanently in January 2017.


title: G8

text: The G20 major economies leaders' summit has had an increased level of international prestige and influence. However, British Prime Minister David Cameron said of the G8 in 2012:


title: G8

text: Some people ask, does the G8 still matter, when we have a Group of 20? My answer is, yes. The G8 is a group of like-minded countries that share a belief in free enterprise as the best route to growth. As eight countries making up about half the world's gross domestic product, the standards we set, the commitments we make, and the steps we take can help solve vital global issues, fire up economies and drive prosperity all over the world.


title: G8

text: The Y8 Summit or simply Y8, formerly known as the G8 Youth Summit is the youth counterpart to the G8 summit. The summits were organized from 2006 to 2013. The first summit to use the name Y8 took place in May 2012 in Puebla, Mexico, alongside the Youth G8 that took place in Washington, D.C. the same year. From 2016 onwards, similar youth conferences were organized under the name Y7 Summit.


title: G8

text: The Y8 Summit brings together young leaders from G8 nations and the European Union to facilitate discussions of international affairs, promote cross-cultural understanding, and build global friendships. The conference closely follows the formal negotiation procedures of the G8 Summit. The Y8 Summit represents the innovative voice of young adults between the age of 18 and 35. At the end of the summit, the delegates jointly come up with a consensus-based written statement, the Final Communiqué. This document is subsequently presented to G8 leaders in order to inspire positive change.