Illusive Mind

The Unquestionable should be questioned

Thursday, May 26, 2005

Evolution, Altruism and Ethics


In this essay I will outline what I regard as the most successful attempt to explain the evolution of altruism. I will then illustrate some of the effects that an evolutionary account of moral behaviour has on cognitivist and noncognitivist theories of ethics. I will argue that evolutionary theory does not undermine Hume’s noncognitivism but supports it and casts doubt on Kantianism.

Evolutionary Explanation of Altruism

Altruism is a term that is used in a wide range of ways. In its strictest application it is taken to mean those actions an organism performs from which they derive absolutely no benefit nor reward. This is a needlessly narrow definition. In The Selfish Gene Richard Dawkins (1976 p.2) argues the mechanics of evolution take place at the level of the gene and that the natural selection favours genes that maximise inclusive fitness, that enable it to reproduce the greatest number of viable offspring possible. With such an ostensibly selfish account of human behaviour the problem of explaining the existence of altruism emerges. Within this context altruism need only mean when an organism (human or non-human) acts to promote other’s interests to the apparent detriment of their own interests and this is how altruism will be used in this essay.

There have been different theories that attempt to explain altruistic behaviour such as David Barash’s account in The Genetic Basis of Kinship. Barash (1976 p.63) argues that sacrificing our own interests for our genetic relatives is consistent with evolutionary theory because such actions increase the chances of genes shared between relatives. This explains nepotist altruism directed to family members known as ‘kin selection’ but not altruism directed at non-relatives as is commonly seen in human societies and advocated by many normative theories.

The problem of altruism is reconciling evolutionary theory with the existence of organisms that promote the interests of non-relatives (or extremely distant relatives) to the apparent detriment of their own. The most successful evolutionary account of this ‘non-related’ altruism has been ‘reciprocal altruism’ introduced by Robert Trivers in The Evolution of Reciprocal Altruism. Trivers (1971 p.83) argues that it can be advantageous for an organism to incur a cost to their own life (eg. giving up food, or risking death) for another non-related organism if the favour is repaid (so long as the benefit of the sacrifice outweighs the cost.) For example a person who saves their neighbour’s child from drowning may increase the chances of their own children’s survival if the action is reciprocated, or intends to be reciprocated.

Reciprocity is important, because natural selection would select against those organisms that would help organisms irrespective of any benefit to themselves. Dawkins (1976 p.197) uses the example of a species of bird that is parasitized with a fatal type of tick. A single bird can remove the tick from every part of its own body except its head where it cannot reach. Consequently the bird can only ensure ongoing survival if another bird removes the tick for it.

An “indiscriminate altruist” or “sucker” as Dawkins calls it, is a bird who will remove the tick from anyone who requires it. A “cheat” is a bird who will happily let birds remove the ticks but will not reciprocate. Dawkins claims that natural selection will surprisingly favour the cheats over the suckers because they can spend more time gathering food instead of grooming other birds. Of course, after the suckers become extinct the cheats will also become extinct because the ticks are not being removed. However the ‘reciprocal altruist’ or “grudger” is the bird that only grooms birds that reciprocate and remembers and punishes those who do not. That is they will reward organisms that cooperate and punish those that cheat. Given the suitable balance (Mackie, 1978) of grudgers, suckers and cheaters, the grudges will be favoured by natural selection.

This explains why evolution will favour those genes pre-disposed to reciprocal altruism. Peter Singer (1994 p.58) notes that this “helps to explain why reciprocity is found amongst all social mammals with long memories who live in stable communities and recognize each other as individuals.”

Richard Dawkins’ bird model is an evolutionary example of Robert Axelrod’s Tit for Tat theory (1984) that supposes that the most rational course of action for an iterated prisoner’s dilemma is to co-operate at first and then punish uncooperativeness and reward cooperation respectively.

It is worth noting that this account of altruism does not explain why many varieties of human morality idealize the character of a person who sacrifices themselves entirely for the good of others and not for any apparent reciprocal benefit. It is also not obvious how this account of reciprocal altruism can explain aspects of human behaviour such as forgiveness. However I will not be exploring that in this essay and will suppose that this account of altruism is equivalent to an account of human moral behaviour.

Impact on Meta-Ethics

What implications does this evolutionary account of altruism have for meta-ethics? In Evolution and the Basis of Morality, Colin McGinn (1979) claims that if morality is to have any independent authority it needs to be associated with reason as cognitivists such as Kant do and not with desires as noncognitivists such as Hume do. This argument suggests that if moral truths can be derived from reason in the vein of Kant’s categorical imperative (1949) then the validity of these truths is not brought into question by the evolutionary explanation of moral behaviour. The argument posits that these truths are objective and independent of human cognition so it is therefore irrelevant how organic the process of our acquiring these truths may be.

McGinn suggests that the evolution of morality can be understood if we consider morality as inseparable from reason, if we suppose, “that the Kantian thesis is right that rationality implies moral sense” (1979, p.165). He postulates that reason has endowed human beings with a host of advantages, and morality is one of the consequences of being a rational being. Morality can therefore be considered a spandrel analogous to the weight of the human brain. The weight of the brain may not itself be evolutionary advantageous but it is a necessary by-product of the cognitive functioning that is advantageous (Gould 1991, p.53).

For McGinn morality is not itself evolutionary advantageous and is at odds with the process of evolution. He thinks this is because morality entails altruistic desires that contradict inherited characteristics “whose evolutionary function, as predicted by gene selection theory, is confined to benefiting the individual and its kin.” His argument can be formulated syllogistically:

P1. Morality entails altruistic acts to non-related organisms
P2. Evolution forbids altruistic acts to non-related organisms
P3. Desires are derived from Evolution

C. Morality cannot be derived from desires

According to McGinn, morality can therefore only be derived from reason, because it has the power to “incline us in a direction contrary to that designed by the laws of natural selection.” The problem with this is premise two has been proven false by the evolutionary explanations of altruism I have detailed above.

McGinn is questioning the authority of the noncognitivist account of morality on the grounds that it fails to be impartial. McGinn is assuming a cognitivist account of morality in assessing the credibility of noncognitivism. He says, “the requirements of morality are such so as to be acknowledged by any rational being” (1979 p.164). The question begging fallacy can be clearly illustrated below.

P1. Morality requires impartiality /objectivity (cognitivism)
P2. Noncognitivism describes a non-objective morality

C. Noncognitivism is false

McGinn advocates a Kantian conception of morality because it has the necessary objectiveness to rise above the subjective motivations selected for by evolution. If we suppose that our desires to do good are all reducible to evolutionary pressures, a Kantian would be forced to conclude that it is impossible to conduct actions of any moral worth or credibility.

For Kant an action done out of inclination or from your particular emotional constitution has no moral worth. (1949 p.126) It is not moral for a person to undertake kind acts because he is inclined to do so as a consequence of his sympathetic constitution. Kant suggests that an action can only have moral worth if there is no direct inclination to do so and if it is done purely out of duty. Kant thinks tt is not enough that we may claim our motives are derived from reason, for our inclinations still affect our will. Therefore only a person with no inclination or an aversion to do good can conduct actions of moral worth.

The argument may be formulated as follows:

P1. All human beings have evolved inclinations that motivate us to do good
P2. A person with inclinations that motivate him to do good is not moral

C. All human beings are incapable of being moral

Even if we concede that not all people have beneficent inclinations, this absurdly restricts all moral worth to only those people with amoral or immoral inclinations.

The Authority of Evolutionary Baggage

It may be argued that a noncognitivist account of morality lacks authority because the subjective desires upon which it is based are just ‘evolutionary baggage.’ This means that my intuitions about caring for my family may just be the strategy of my genes to optimise their perpetuation.

But on what basis is their authority really being questioned? Hume doesn’t suggest that we have complete control over our desires. He admitted that the feelings upon which our moral judgements are based are “certain instincts originally implanted in our natures” (1888 p.121).

Does the influence of evolutionary pressures on our subjective moral judgements undermine their authority? If you agree that morality should be impartial then you already think Subjectivist morality has no authority. If you are a Subjectivist then you think moral judgements have authority to the extent that they convince us. You would think that moral judgements have authority with respect to others only to the extent that they share our sentiments. The evolutionary explanation of our ‘instincts’ would not perturb Hume who says that:

“A man naturally loves his children better than his nephews, his nephews better than his cousins, his cousins better than strangers, where every thing else is equal. Hence arise our common measures of duty, in preferring the one to the other. Our sense of duty always follows the common and natural course of our passions.”

Hume 1896 Part II. Section I.

The problem that an evolutionary account of morality raises is that unless we postulate the existence of objective moral truths it makes moral judgements arbitrary. Our passions are determined by an arbitrary, blind and random mechanism. If the evolution of our species had altered it is likely that our moral intuitions would also have changed accordingly.


If you accept Hume’s thesis that all moral judgements are ultimately reducible to a desire or passion, then the contents of moral judgements are arbitrary. But, so are the contents of human societies and behaviour, they too are products of evolutionary processes that could have turned out differently.

They are arbitrary in the sense that evolution could have made alternative phenotypic variations if circumstances were different. Suppose that the human reproductive cycle was the same as that of a rodent’s. That in order to prevent regular mass overpopulation we would have to kill those offspring who were genetically weakest. It stands to reason that are moral intuitions regarding the obligation towards children would be markedly altered.

However, moral judgements are not arbitrary in relation to how they correspond to human evolution. My intense desire to survive correlates to the evolutionary predisposition for genetic perpetuation. Human intuitions could not just be anything; they are adaptations that favour the survival of human genes.

It is irrational to get rid of my desire to survive just because my motivations are arbitrary. My intense desire for survival may just be a stratagem of my genes for optimal perpetuation, but that itself does not make it rational to commit suicide.

Evolutionary psychologists hypothesize that a fear of spiders is one example of evolutionary baggage. Our species happened to reside in an environment where spiders were responsible for many fatalities. Consequently those persons with genes that predisposed persons to fear spiders and restrict their contact with them would be favoured by natural selection (Oshman, 2001).

It is rational to dump the evolutionary baggage of a fear of spiders, not because it is arbitrary but because it is unwanted. Having terrifying arachnephobia is no longer needed when we are quite able to distinguish between harmful and harmless spiders and for the most part no longer reside in an environment where they pose a great threat to our survival.

My morality is as arbitrary as my left hand; through a random process of genetic mutation it has evolved as an adaptation because of its ability to increase my genetic fitness. Morality is still useful just like my left hand, and it is as irrational to stop using morality because of its origins, as it is to stop using my left hand. Of course I can stop using my left hand if I want to. The arbitrariness of moral distinctions only serves to undermine a cognitivist theory of ethics that supposes that moral judgements are not arbitrary but objective laws independent of human cognition.

The question of retaining moral judgements then is reduced to a question of desire. Do we want to utilise judgements whose agenda is the ongoing survival of the species (at the level of the gene) through a system of rewarding co-operation and punishing cheating?

Hume wrote “’Tis not contrary to reason to prefer the destruction of the whole world to the scratching of my finger.” Thus for a noncognitivist like Hume, it is neither irrational nor rational to be moral. Consequently, there is no rational basis on which to criticize the amoralist who does not care to make or be bound by moral judgements.

It may be argued that my desire to submit to the figments of evolution is itself influenced by those figments. However I am supposing that the influence is not so great that I am unable to freely make a choice. If this were not the case, the debate over making moral judgements would be moot as the ability to be moral and make decisions it premised upon moral agency, upon freedom of will.


The only way to be objectively moral and avoid ‘evolutionary baggage’ from tainting our moral judgements seems to be to devote oneself completely to reason in a Kantian fashion. However, it is not a forgone conclusion that reason is above evolutionary pressures. In The Evolution of Reason, William Cooper argues, “the laws of logic emerge naturally as corollaries of the evolutionary laws” (2003, p.5).

If you accept Kant’s thesis that moral judgements can be conducted entirely without emotion, and suppose that the faculty of reason itself is not littered with evolutionary baggage, then it is rational to formulate your moral judgements in this way. Reason will allow you to perceive ethical reality and rise above the delusions of our biological influences. For a cognitivist like Kant it is rational to be moral, because morality itself is a consequence of the laws of reason.

However, there are serious doubts about how the human brain fashioned through the organic process of evolution can happen upon the ability to perceive a logical reality independent of human experience. Konrad Lorenz writes:

“Kant’s statement that the laws of pure reason have absolute validity, nay, that every imaginable rational being, even if it were an angel must obey the same laws of thought, appears as an anthropocentric presumption.”

(Quoted in Cooper, 2003, p.16)

If Cooper is right in insisting, “logic is not extra-biological but wholly emergent from evolutionary processes” (2003, p.13) then noncognitivists like Kant are left with no human faculty with which to escape the arbitrariness and subjectiveness of human behaviour and moral judgements.

Evolutionary theory would debunk moral realism, but not moral theory as described by Hume. Philosopher and Neuroscientist Joshua Greene writes, “we can understand our inclination towards moral realism not as an insight into the nature of moral truth, but as a by-product of the efficient cognitive processes we use to make moral decisions.” (2003, P.848)

In this essay I have outlined what I regard as the most successful attempt to explain the evolution of altruism. I have illustrated some of the effects that an evolutionary account of moral behaviour has on cognitivist and noncognitivist theories of ethics. I have argued that evolutionary theory does not undermine Hume’s noncognitivism but supports it and casts doubt on Kantianism.


Axelrod, Robert (1984) ‘Tit for Tat’ in Peter Singer (ed.) Ethics, Oxford: Oxford University Press p.88-92

Barash, David (1979) ‘The Genetic Basis of Kinship’ in Peter Singer (ed.) Ethics, Oxford: Oxford University Press p.63-6

Cooper, William S. (2003) The Evolution of Reason, Cambridge: Cambridge University Press

Dawkins, Richard (1976) The Selfish Gene, Oxford: Oxford University Press

Greene, Joshua (2003) ‘From neural ‘is’ to moral ‘ought’: what are the moral implications of neuroscientific moral psychology?’ Neuroscience, Vol. 4, p.847-50

Gould, Stephen J. (1991) ‘Exaptation: A crucial tool for evolutionary psychology’ Journal of Social Issues, Vol. 47, p.43-65

Hume, David (1888) ‘Reason and Passion’ in Peter Singer (ed.) Ethics, Oxford: Oxford University Press p.118-23

Hume, David (1896) A Treatise of Human Nature, Oxford: Clarendon Press,
http://oll.libertyfund.org/ToC/0213.php (accessed 19 May 2005)

Kant, Immanuel (1949) ‘Pure Practical Reason and the Moral Law’ in Peter Singer (ed.) Ethics, Oxford: Oxford University Press p.123-31

Mackie, J.L. (1978) "The Law of the Jungle: Moral Alternatives and Principles of Evolution", http://www.royalinstitutephilosophy.org/articles/mackie_jungle.htm (accessed 19 May 2005)

McGinn, Colin (1979) ‘Evolution and the Basis of Morality’ in Peter Singer (ed.) Ethics, Oxford: Oxford University Press p.164-6

Ohman, A., et al. (2001) ‘Emotion drives attention: detecting the snake in the grass’, Journal of Experimental Psychology: General Vol. 130(3) p.466-78

Singer, Peter (1994) Ethics, Oxford: Oxford University

Trivers, Robert (1971) ‘The Evolution of Reciprocal Altruism’ in Peter Singer (ed.) Ethics, Oxford: Oxford University Press p.78-88

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Blogger Steve said...

Very good essay.

I think the evolutionary moral impulses may be less arbitrary than you imply (of course I agree they are not a source of objective truths). It may be that most or all social animals would share many of the same impulses, and further, it may be that being a social animal was a key ingredient to achieving a high intelligence.

In any case, your take on Hume and Kant is interesting and your concluding sections make good points. I would more explicitly add that it is cultural evolution which provides an engine for further phases of moral development which integrate the moral impulses from physical evolution with our further reasoning about such issues derived from our higher cognitive skills.

6/01/2005 08:55:00 AM  
Blogger Illusive Mind said...

Hey Steve,
Thanks for the comment.

You may be right that some form of reciprocal altruism is necessary to the development of social animals. However even this would be an empirical claim, that whilst having a strong correlation to the natural world is itself arbitrary.

Why? Because if the planet was a little bit warmer or a little bit colder, maybe we would more efficient food resources which would have allowed more energy to be directed to the brain, and maybe we could have (we might still) develop a form of telepathy whereby it would be impossible to lie and cheat and reciprocal altruism would not be required.

This is an undoubtedly convoluted example, but I think the point is that our behaviour is entailed by organic and alterable processes and not some objective schema.

I think you’re right to suggest that human morality is based upon a cultural evolution that allows reasoning and higher cognitive functions. We don’t just emotionally react to everything we come into contact with. If I had more room in the essay I would’ve talked the false dichotomy between Hume and Kant, they both want to hold onto one end of the spectrum of the reason / desire split to the exclusion of the other.

I explore this a little in Subjectivism: Some problems

6/01/2005 05:57:00 PM  
Blogger P.A.Aneesh said...

I enjoyed reading you. The essay is excellent.

7/22/2009 10:47:00 PM  

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