Wednesday, June 06, 2007

How free are we?

You’ll notice that I have rephrased the question ‘is there a free will?’ from its binary form into an analogous query that forms the title of this post. This question has decidedly created countless debates and zillions of web page discussions among the philosophers and the religious. I, however, will address this question, purely, from a biological point of view which is probably the only legitimate perspective, if you care for truth i.e. Let’s start with definitions; admittedly there are many variants of free will, but in order to avoid getting into a vicious (or virtuous) and circular philosophical arguments- let’s define free will as the ability to choose your future course of action independently.

Any discussion of free will usually has to address two issues; one semantic and another conceptual. The issue I refer to as semantic is the one that deals with our identity; clearly when we say free will, we also have to answer ‘whose’ free will we are referring to. For millenniums, Hindu Philosophers (probably folks from other religion are at it too) grappled with this question ‘Who am I?’ and waxed eloquent about the life-changing implications of inquiry into our identity. The answer, as it turns out, is pretty simple, we are bipedal primates belonging to the mammalian species ‘Homo Sapiens’. The reason why there continues to be a debate in the spiritual circles is the following- ‘I have a leg- therefore I am different from my leg, I have a brain- therefore I am different from my brain, so I must be a soul who has a body’. A little bit of thinking reveals that the problem is purely semantic- the brain refers to itself in the third person to avoid going into circles, that’s all. A robot can be programmed to say ‘I have an onboard computer; therefore I am different from it, etc’; but doesn’t mean anything.

But are we robots then; here we need to address the second issue- the conceptual one. Most people have a polarized view on free will- either they believe in determinism or freedom. Fortunately another perspective is possible, only it’s not an ‘ism’; I refer to the category of things (both living and non-living) that can be ‘programmed’. As somebody who is addicted to playing chess with the computer, I can’t think of a better example than computer chess to illustrate my point. Most people think the reason Deep Blue could beat Kasprov was because it could evaluate 35/40 moves (the entire game) for all combinations; frankly that is impossible. The number of possible ways the first 35/40 moves could be played is larger than the number of atoms in the universe; to evaluate all the possible combination of the first 10 moves itself would take close to 1500 years for the fastest supercomputer today. No, it doesn’t quite work that way, programmers provide heuristics/thumb rules to shorten the decision making process. These rules, by the way, have a small but finite probability of misfiring under specific circumstances- but mostly they work well. Also once the programming is complete, the programmer is not allowed to help the computer during a competitive game. This is probably the closest analogy to how our brains work; our brains are programmed by genes and memes (cultural equivalents of genes). The programming consists of a set of instructions, heuristics, rules of thumbs etc., but once we are born, we are on our ‘own’. No gene would actually whisper instructions into our ears, but the programming creates a statastical bias to behave a certain way- which again gets modified under cultural influences. Now here comes the interesting part- the set of rules is finite, but the range of behaviors possible is practically infinite like the total number of moves possible in chess. Thus the unpredictability of these infinite emergent behaviors arising from a finite set of rules is what that gives rise to the illusion of free will/control over our actions.

But this world-view creates a few sticky problems of its own, chief among which is explaining how we can hold people responsible for their actions if free will was only an illusion. One must appreciate the fact that morality is purely a human affair, and therefore we can’t look to biology or science for answers. But we do know that human behavior responds to incentives and penalties, therefore having a robust legal system may be only way to regulate behavior in absence of free will!