Saturday, October 03, 2015

Free Will, whatever that is

There has been quite a few papers and books on the existence of Free Will, it is a common topic of discussion and even an accepted scientific endeavor. The debate about free will has been around for ages, from the theological debates of Calvin and even Aristotle and Epicurus before him, to recent books by atheists such as Dennet and Sam Harris. A quick search in Google Scholar produces more than 370 thousand papers, 8 thousand so far in 2015 alone. Free will is described by dictionaries as "the power of acting without the constraint or necessity of fate" an overtly religious concept, or on the more acceptable coercion side "the ability to act at one's own discretion."

Leaving aside the coercive aspect, when I hear "free will" the first thing that comes to mind is "free from what?" It is hard for me to conceive of those two words together in a way that does not say "Theism," outside of a theistic or metaphysical context what is the frame of reference from which will is freed from? What other sense can be given to these words in a way that makes sense in a secular context? in a natural context? in a scientific context? If it is not god then what? All of the arguments that I have seen put forth superdite it to be the antonym to "Determinism" the notion that everything is predetermined by previous conditions. But this denotes a misunderstanding of the limits of determinism itself. A physical system being "deterministic" is not the same as having around the omniscient observer from the theological arena. Philosophical determinism does not exist in reality. Determinism does not imply predictability.

The limits of determinism

Determinism is the philosophical idea that causes and effects are unequivocally linked. That a set of causes can produce no other effect. Human-made systems tend to be strictly deterministic and predictable because that makes them much easier to design. Any deviation into a regime in which things become unpredictable, for example air turbulence on a wing or jet turbine or around a bridge, and our creations become unstable and very likely to get destroyed. But such idea of determinism does not apply to natural physical systems, beyond some toy problems or extremely narrow classes of systems it is very likely that we will encounter something completely different.

A coin flip is a deterministic system. All the variables, all of the effects, are strictly physical, relatively simple, and can be described by known physical equations. However we call such a flip "random" because it is impossible to predict. The outcome of a coin flip, though deterministic, is clearly unpredictable. Those that believe in the clear-cut notion of determinism believe that if we were able to know all the conditions around the coin, exact initial conditions, and exact environmental influences, we would be able to predict the outcome of any coin flip. What they ignore is that the precision required for such knowledge is impossible. Practically impossible and theoretically impossible. Yes we might have equations for it but systems such as this show what is known as "sensitivity to initial conditions." No matter how small the error in our knowledge of the physical variables is, which is unavoidably limited by Heisenberg's uncertainty principle or much before that by the errors introduced by environmental thermal noise, such uncertainty will get exponentially amplified by the system until it shows real and clear effects, such as the randomness of a coin flip.

This sensitivity to initial conditions was dubbed "The Butterfly Effect" when the first evidence of chaos in a natural system was found in the deterministic equations being used to model the weather by Lorenz in the early 1960's. Poincaré had postulated the existence of such effects in 1890, but it had remained in the realm of mathematics until Lorenz encountered it in the equations he was using to simulate the weather. It was said that "the flapping of the wings of a butterfly in Brazil could induce the formation of a tornado in Texas." Although it was a model of a physical system—the weather—note that that this evidence of chaos was found in a system made of equations running in a computer. Well-known, well-defined, well-understood equations running in a digital computer, what can be more deterministic than that? The effect was found when Lorenz rounded off the last few digits in some of the data before rerunning a simulation, and obtaining completely different results the second time around.

Chaos theory

Chaos is not randomness, chaos is deterministic. If you want to have an intuitive feel for what chaos is, perhaps the easiest way is to use a simple spreadsheet and plot a chaotic equation as this guy did with the logistic map. Minor changes would give you rather unpredictable trajectories in the long run for what is a perfectly predictable, simple, and deterministic equation in the short term. A minor and apparently insignificant change in initial conditions will be exponentially amplified by the system carrying it to a completely different region of solutions, a different area of its state space (the abstract mathematical space described by the possible values of the variables of the system).

But there is another way that chaos is not randomness, chaotic systems tend to be well-behaved in the sense of not deviating too far from stablished limits. These systems display what are known as strange attractors and orbits that restrict the variables of the system to some region of state space. That is, a random hurricane cannot pop up in the middle of Alaska as such condition does not form part of the possible solutions of the chaotic weather system. Likewise, the Great Red Spot in Jupiter has remained in place for more than a century despite being the product of the same sort of physical chaotic weather interactions.

That is, many statistics of a chaotic system can be well defined, the range of solutions can be well defined, the way it interacts with its environment can be well defined, the orbits (i.e., attractors) of the system can be well defined, even the equations and values of constants of the system can be perfectly well defined, yet after some time horizon that depends on the system itself it will be impossible to predict the exact state of the system. That is why weather (the exact value of atmospheric variables) becomes unpredictable after more than a week or so, while climate (the average and variance of the same variables) can be predicted years in advance. It is the same set of equations, but in one case you are looking at the details while in the other you are looking at the big-picture statistics.

Chaotic systems are a subset of what is known as complex systems, systems that have enough non-linear interactions among their elements that these become difficult to analyze, understand, or predict. While chaotic systems are deterministic and non-random, complex systems can make use of true randomness as well. Complex systems display emergent behaviors that are not obvious from the properties of their elements. A brain can be better described as a complex system. The human brain is a system with 10^11 neurons (very nonlinear elements) with 10^15 total connections (synapses) among its neurons. It is impossible to conceive of a system of such complexity to not be chaotic, and indeed it has been shown to be chaotic at many different scales. It should be clear that nature does not care about "understanding" what it builds. If nature finds a way to exploit what we might see as a problem for designing a system, such as chaos, complexity, or randomness in order to obtain an advantage, it will.

Note that this means that regardless of how much information we have about a brain, given enough time (which can be mere seconds), it is impossible to predict the exact state it will be in (even for the brain itself). That is the classical philosophical conception of determinism, or simple causality as infinite predictability, makes no sense when it comes to a complex physical system, to a brain in general, and to a human brain in particular. Chaos theory is enough to get rid of such simplistic notion.

But if that does not feel to be enough to get rid of such invalid notion of determinism, in the most evolved areas of the brain actual randomness takes place. Synaptic transmission can be randomly ignored up to 70% of the time. That is the firing of a neuron can be ignored by another connected neuron the majority of the time. Other types of synaptic noise and random firings are also present in multiple areas of the brain due to effects that have to do with thermal and chemical noise at the synaptic level. That is, true randomness. This does not mean that the brain is random, it just means that randomness is an intrinsic part of the brain's operation. We do the same thing by using randomness in our favor with dithering, as engineers call it, or stochastic resonance, as physicist call it. But in the case of the brain, beyond the sensory organs where stochastic resonance has been shown to enhance signals, we have no real idea of randomness' function, if it has any.

Combine randomness, chaos, and overall complexity, and any naïve notion of determinism as predictability must be thrown out the window. Theoretically, all it takes is a random alteration of the environment, the chirp of a bird, the passing of a car, the rustling of a leaf, to change the space of decisions that a brain can attain. Further, internal thermal noise makes even those external influences unnecessary. A minor alteration in any of our senses, or none at all, could place our brain in a completely different area of its state space. In a completely different range of ideas and considerations. The real question should be how does it manage to stay so consistent and limited in its range of behaviors, with all of the chaos and randomness that is going on inside it?

Does the fact that philosophical determinism does not exist in reality mean that we have "free will"? well as I have said, I cannot conceive of a definition of those two words together that makes sense. I have shown above that the supposed antonym "determinism" does not make sense as part of a definition because "determinism" itself in the physical sense leads to it being synonymous with the term we were trying to define. The brain is deterministic, complex, chaotic, and uses randomness to boot. As any other real physical complex deterministic system does. The brain is not free of its ties to nature itself.

What about Superdeterminism?

The notion of superdeterminism is that if you look under the quantum level, there can be an underlying reality that is fully deterministic. This notion goes beyond the local variables of Bell's theorems into an unknown sub-quantum level that might precisely determine the result of every experiment. Theoretically, such a notion could thus bypass the uncertainty principle and allow us to conceive of infinite precision measurements. This is basically what Einstein had in mind when he said "God does not play dice with the universe" (which was directed specifically towards the Copenhagen interpretation, not to quantum theory as a whole).

But note that even if this was the case, there is no reason to think that a complex system, made of many complex parts, such as the universe, would not remain chaotic, and it remains impossible for a finite observer to make an infinite precision measurement (Heisenberg's principle and quantum equations are already a testament to this). So the same caveats made about determinism still hold, not only for the brain but for the universe as a whole. Thus, even in the case of superdeterminism, the notion of being able to accurately predict the long term behavior of a complex system remains in the realms of the infinite omniscient beings of theology. Which might, or might not be, part of your personal reality.

There is free will then?

If the discussion is limited to the realm of philosophy where the original question was posed, we have no more options than to answer: maybe, only a Sith deals in absolutes. Given that physical deterministic systems cannot achieve the conception of philosophical determinism, then it would seem that we only have one alternative left. However, when people talk about "free will" it is not under such clear semantic constraints. It is at least subconsciously interpreted as being free from what the rest of nature goes through. We, humans, are different from the rest of nature because we, humans, have free will. Which is clearly not the case. We are not free from the constraints of nature, it is nature itself that is free from philosophical determinism, freeing us in turn.

But we should not be jumping to conclusions, even though philosophical determinism does not exist this only applies to mental weather, mental climate would still be mostly deterministic in the philosophical sense. So, even though no one can predict what precise action would be taken at any given moment (mental weather), we can have a very good idea of the set of constraints and considerations that will form part of taking such action (mental climate). Even though the weight we give to different considerations will change from minute to minute depending on our mood, our goals, our hopes, our dreams, our expectations, our level of awareness, how hungry we are, ambient temperature, that itch behind our left ear, etc., the range of actions we will take and the range of weight we give to the multiple considerations will be constrained by our previous experience and the specific situation. Thus, even though philosophical determinism does not exist when it comes to the mental weather, it sure applies to a higher or lesser degree when it comes to the mental climate. Thus we have to go back to the question: how could we define free will in a way that can make sense?

Note that this has little to do with the free will philosophical notion of incompatibilism. This notion assumes that "free will" makes sense as a term. It postulates that a deterministic universe makes free will impossible. Which still makes use of a naïve notion of determinism and the flawed definition of free will. But we could still contemplate the philosophical notion of compatibilism (or soft-determinism), which attempts to solve the dichotomy by seeing free will as the ability to act under our own motivations.

Compatibilism is an attempt to redefine free will in a way that makes it compatible with a deterministic universe and thus removes the logical contradiction. Compatibilism, at its origin, basically denies the existence of the traditional notion of free will by moving the boundary towards "acting based on our motivations" (mental weather) while at the same time conceding that our motivations are pre-determined in a deterministic universe (mental climate). In other words, compatibilism amounts to "free will is illogical and thus non-existent, so lets redefine the term in a way that remains usable." More modern versions of compatibilism have moved this boundary into the classification of our motivations so that our actions are free or not based on the types of motivations we follow.

If we take "free will" to mean instead (as the compatibilists do) that we make conscious decisions under our own motivations, we immediately run into trouble both with the definition of consciousness as with the origin of our motivations. Consciousness is an emergent property of the complex system that is our brain, and it has been deemed the holy grail of neuroscience. One of the biggest open problems in science. We do not really know what consciousness is, so how can we use it in a definition? We could use the poetic description "what it feels to be a brain" but then that becomes useless in terms of defining free will.

There have been brain imaging experiments in which it has been shown that decisions can be predicted a full seven to ten seconds in advance of our being conscious of them. That is, we think that we are making a decision at some point in time, yet the brain images show that the decision had already been made at least seven full seconds before that. Way before it arises to our consciousness. That is, unknown to our conciousness, our brain has already made a decision that we still perceive as being "free." These experiments strongly suggest that what we see as "consciousness" is just a mental model of other deeper processes that are taking place in our brain, a rationalization that allows us to "understand ourselves." Nothing but the persistent illusion of a brain modeling itself. If we rely on consciousness to define it, free will would just be an illusion.

Thus, lacking any useful definition we go back to "free will" still making no sense, except perhaps as a synonym of "without coercion". But in this era of propaganda and manipulation, how much coercion can be acceptable for our will to remain free?

What's the alternative?

Instead of talking about free will in such an absolute sense we should be talking about how correlated, or how statistically independent, are our decisions from specific subsets of our experience. How free to act from a specific set of pre-existing social and psychological conditions are we. How much free will do we have in a specific situation. As a deterministic system if we ignore measurement limits and the existing randomness of the brain, it should be clear that if we were able to capture all of our experience and genetic factors we should be able to create a physical model that could exactly predict our actions. We are a product of nature and nurture, our decisions are as well. But it is also clear that such mental experiment is practically and theoretically impossible to carry out in reality and we would remain unpredictable and "random" within a reasonable range of constraints. Determinism does not imply predictability, let's keep that in mind. However, just as with the weather and the climate, it might still be possible to have usable and valuable models that can help us with the tasks of short-term and long-term predictability.

We can still make statistical models of childhood interventions, educational techniques, psychological techniques, and many others (including advertising and propaganda) that would allow us to assess the degree and importance of correlations to our mental and decision processes, to our mental climate. With the help of EEG and brain imaging in modeling such interventions, it should become possible to measure, predict, and intervene in "brain climate" even if "brain weather" remains mostly unpredictable. It is this "brain weather" that gives us the apparent illusion of free will.

Perhaps the system most affected by all of this is the penal system, in which free will is seen as synonym of intention, the difference between murder and manslaughter, between innocent by cause of temporary insanity or guilty due to a faulty morality. It is within this penal system that compatibilist ideas make sense, by moving the boundaries of determinism deeper within the mental processes we can feel better about punishing others because they were exercising more or less "free will." Free will is, after all, what underpins our concepts of morality.

But, as our knowledge of neuroscience advances, as our knowledge of what is knowable leaves the idealized deductions of philosophy and enters the reality of science, our laws and penal systems would have to adapt as well. As any complex system does. As science advances it might be possible to design intervention techniques for "morally deficient" individuals that bring them into better compliance with society, as some psychology practitioners are already doing. We could find interventions, and feedback mechanisms, that would bring the mental climate of a felon more in line with general society.

The Buddhist perspective

It should be of no surprise that having no need for external gods that influence and punish our actions, Buddhism had no need to posit an absolute idea of free will as a way to sidestep the impossible theological problem of having infinite punishment with an omniscient god. But within the context of Buddhism, it is possible to reach a compatibilist definition of free will that could make sense from a scientific psychological perspective. Alan Wallace has done as much (paper here), and he provides a good summary of the history and problems around the term "free will" in that 23-minute video. As anything in Buddhism, there is a middle way.

Just as suggested, we could define free will as a degree of freedom for our thought process. Not if we have free will or not but how much do we have, how could we have more of it? under what conditions we would have less of it? and how could we train our children and society to have more of it? We could define free will as the degree of freedom from the five mental obscurations, namely: delusion, craving, hostility, envy, and pride. The less of those mental obscurations we have, the freer our will becomes, the wiser our actions become. Thus reaching absolute "free will" would become equivalent to the buddhist enlightenment, what could be wrong with that?... Yes, a bit of sarcasm (just in case). We would be basically moving from the religious context of the west and the free will of christianity, to the religious context of the east and their more natural view of mind processes based on causes and conditions.

Note that such definition would move the boundaries into an area that would remain compatible with our fuzzy existing notions of "consciousness." It would not matter how conscious or not you are of your decisions, even if your apparent decisions are the consequence of automatic reactions, for a well-trained "free" mind, these actions would have been taken with the right "frame of mind" (mental climate). And thus could still be rationalized a posteriori as "free" even if subconscious. In other words, such definition would not depend on our illusion of conciousness and our lack of understanding of it.

As with any other compatibilist definition of free will you can take it or leave it, but I don't see any other range of possible definitions that makes sense, allows for operant psychological interventions, and accounts for our sense of morality. You could argue that mental obscurations are just part of the Buddhist religious dogma, you would be right, but then feel free to offer a better alternative, or choose a different set of "obscurations" that does not suffer from the same problems. Other compatibilists have tried to no avail. That is how science works after all. Collectively agreeing to a definition that follows in this line of thought would be a step in the right direction and remove a lot of obfuscation from a very crowded field. Otherwise we should just stop talking about "free will" altogether.

In conclusion

Even though we do not know how to define it we all like to think that we have free will, that we are not constrained by our circumstances and our upbringing and that at any moment we can make a decision that changes our destiny. Of course we can, but it is naïve to think that such decision happens in a vacuum, there will be a set of circumstances that will allow us to get into the needed mental framework (mental climate) that lets us make such decision (mental weather). As chaos theory predicts, a minor decision today can have major consequences for our mind and our life tomorrow. Our whole mindset can change, the way we look at the world can change, the way the world looks at us can change, all starting from a comparatively minor decision. That is the flapping of the butterfly in the amazon forest starting a tornado in Texas. This further fortifies the notion of "free will." We ignore that such decision was conditioned and caused by the circumstances that surrounded it and we give ourself all of the credit for making such a huge change in our life. We rationalize our very personal decision as the "cause" of the change, what got everything started. Yes, the decision was ours, yes the choice was ours, yes the morality that made it happen was ours, but it did not happen in a vacuum disconnected from the physical world.

In a sense, we need the apparent illusion of "free will" the same way that we need the illusion of "conciousness." Knowing that we have control over our destiny, and having such construct as part of our mental climate, allows us to make decisions (mental weather) that we would not be able to do otherwise. Feeling constrained by fate will serve to reduce our freedom of action, feeling that we have our fate in our own hands increases our freedom of action. In a sense the more you believe in "free will" the freer your will might become. It is the difference between short-term and long-term predictability and our notion of causality. In a deterministic system, predictability goes both ways in time, we cannot "predict" what the historical events in our life put us in the situation (mental climate) we are currently on. We cannot "predict" the series of events that molded our morality, our ethics, our notions of good and bad, our notion of value and importance. We cannot rationalize, assign clear cause and effect relations, to all of the myriad interactions that molded our view of the world. Thus, at the present moment our will is "free" as it cannot be predicted by the past. The present storm in our mental weather cannot be causally connected to any series of individual events by our conciousness, even though it naturally is.

"Free will" is part of a belief system, a moral choice, a religious decision. "Free will" comes from postulating a metaphysical "fate" a religious construct and from justifying moral punishment around such construct, and we see that we can only define it inside religious constructs, belief systems, and moral systems. This idea that will is "free" comes from the flawed notion of thinking of "determinism" as being equivalent to predictability. If we say that something is pre-determined we are basically relying in our flawed notions of cause and effect to say that it is predictable from the current set of conditions. But real, physical, determinism does not work that way. Real determinism does not imply long term predictability. If we focus on specific circumstances in our history, those circumstances determine how we are going to act (our mental climate) but cannot predict what we are going to do (our mental weather). The proper 1-minute interaction with a random "teacher" along the way might be enough of a butterfly to put our mind in a tornado of change a few years down the road, even if we have no recollection of it.

From the point of view of determinism our will is not "free" it is always constrained by our upbringing and our circumstances. It is always constrained by nature. But such constraints are not destiny, are not fate. Such constraints limit our range of action in the present moment, but cannot absolutely constrain what the effects of a series of small decisions can be. Just like a hurricane track in a weather report, you will have a very good idea of were you will be tomorrow based on present circumstances, but a small nudge to the east or to the west can completely change where you will be a year from now. In a sense our will is only as constrained as the limits our mind puts on it, the freer you think you are the freer you will be. But be careful, mental institutions are filled with people whose freedom of will exceeded the bounds of reality.