Friday, March 11, 2011

Free will in the genomics age: does it have any meaning?

In the March 10 edition of the BBC Radio 4 program In Our Time, the three guests discussed the subject of free will.  Does it exist?  Could it exist in the age of science? Or is it just a mistaken notion that is a hangover from religion, related to what is needed in order for people to be responsible for their own actions, and hence where they end up in Eternity?

This discussion was by philosophers, not neuroscientists, but the neuroscience and general-science perspective is there.  The discussion is quite interesting.  The idea of free will arises because we so much feel that we have it, that we make decisions.

The issue for us relates to the concept of determinism.  If the universe is completely Newtonian, that is, follows perfect laws at all scales of observation, then everything is related to and in that sense predictable by anything.  At the time of the Big Bang, what you are going to have for dinner was, in principle, predictable.  That would have fundamental consequences for evolution, since in a purely deterministic universe there is no real competitive factor among rabbits and foxes: the slowest rabbit was fore-ordained to be dinner for the fast fox.  Random variation screened by unpredictable experience is not what's going on, despite the Modern Synthesis claims to the contrary!

Of course this is all nonsense, because to see that everything is predictable you probably would have to be outside the universe to observe it, but the  idea of a totally deterministic universe is that it's entirely of itself--no outside agent that could meddle, or even observe it.

Anyway, if this is the world we're in, then nobody is responsible for their actions in the moral sense, not even Stalin or Hitler or Ghaddafi, or Mother Theresa for that matter.  We are determined from conception by our genes, and our environment.  Our neurons wire up during life, in totally predictable ways (predictable in principle, that is, if one knew where every molecule and every neural cell was at every instant, etc.), and so the thoughts we think are just the result of that wiring--not in any sense freely thought by us, if thoughts really are just signals flying around among neurons.

As the discussion in the BBC program points out, even if randomness exists, we aren't morally at free will, because we're the combination of pure physical determinism, plus chance events that we don't control.  Thus the usual appeal to quantum mechanics probability doesn't change the story of determinism vs moral responsibility.

But are even 'random' events like mutation really random?  If they are not, but are just determined in ways we can't understand, the world returns to deterministic laws-of-Nature status.
But what is a 'chance' event?  Is it one with no cause?  Or is there some kind of cause that is probabilistic--clearly something we do not understand?  If, for example, random mutations really follow some laws of probability, then determinism just takes a slightly different form.  Free will remains in the realm of the non-material, and hence mystic and non-existent illusion.

So, if our thousands of genes controlling the behavior of billions of cells, in environments with many chance factors, are just working out the physical forces, there is no such thing as free will, no matter how it feels to us.  If there is true probability (neurons wire to some extent just by chance, truly), then there may indeed be something that would genuinely approach free will: it would not be predictable, even by probability distributions (because the latter would not be pure chance, but a different kind of cause).  In terms we understand, at least, pure chance is an effect without a cause!

More likely, what we're learning by all our omics technologies is essentially that things appear so random, and there is so much of it, that we can never, even in principle collect enough data to predict whether you'll have this or that flavor ice cream today, or whether you'll have chicken or pasta on your next overseas flight.  Even if the appearance of randomness in brains, like that in tossed coins, is really just an illusion of randomness.

It is thus hard to escape that no matter how it looks, all that seems to be free will is illusion, not true free will.  And it's dispiriting to feel that so much of life is an illusion (a view that Darwin is supposed to have expressed, though we don't remember seeing the quote - if you know it, let us know).  But if free will is an illusion, mistaken appearance of causeless effects, then for the very same reasons, so is natural selection.  And that is food for thought, for people as well as the happy, not really just lucky, fox.

7 comments:

Holly Dunsworth said...

Ken,
Have you been a fly on our wall lately? Are our households quantumly entagled by any chance? This is such a timely post!

Thanks so much for it.
Holls

James Goetz said...

Hmm, if causal determinism is reality, then all illusion of probability and freewill has been determined while the determinism had no beginning. Also, all philosophical rejection of causal determinism has always been determined. Additionally, determinism always determined that evidence of determinism and the illusion of probability would always be inscrutable to humans that contemplate determinism.

Nate Davis said...

I'm reminded here of Calvinic theology, which claimed that God, having the qualities of omnipresence and omnipotence, must have knowingly prescribed everything that would ever happen in the universe; for while creation only happened once at the beginning of time, God chose to create it this way and not some other way. Following from this idea, people accept Christ and become believers only because God willed it to be so at the moment of creation. Following even further, God chose who goes to heaven and who goes to hell. Follow it enough and you realize that God created evil, but that was a blindspot most were comfortable with.

More to the point of this conversation, I would argue that if the universe were entirely deterministic, Hitler would still be just as contemptible. If it was his "fate" to act as he did, then it is equally our fate to act as we do against him. I don't see that moral responsibility from the individual perspective changes much. We act as we must.

Is it possible that the universe be partially to mostly deterministic? The usual assumption seems to be largely reductionist; that the more basic scales (e.g. quantum) are also more essential and descriptive. I'm not so sure. Complexity arises from systems. A description of an organism isn't satisfied by a collection of its cells. Certainly, a cell is more basic in that it exists previous to the total system of the organism, but - okay, I lost it. I just mean to say that there might be better ways to go about the question.

One last, more comical point: I had a discussion with a physicist/engineer friend recently, who told me his new theory. If the universe is deterministic enough, its theoretically possible that we could create a simulation of the entire universe, given the right parameters and enough computation power. Since it's a program, we could even just "fast-forward" until we get to our own part of the universe. We could even then go past our own time and figure out any future discoveries in science, humanities, anything. Presumably our simulated universe will have simulated a universe for themselves as well. It would seem to follow that we are ourselves inside a simulated computer-driven universe. If the universe is entirely deterministic, this is all quite possible. Of course, it could be that the simulation we're in only seems as it does because the paramaters were set up as such by bearded wizards, alternate-dimension nerds, or the simulation spaces of a horrific Lovecraftian monster. So it goes.

Ken Weiss said...

If the world is entirely deterministic, then astrology is true (if we only knew enough to read the messages with perfect accuracy). The BBC program did discuss the issues raised by Calvin (and, I think they said, Augustin).

The problem with simulation is that it, too, is part of the universe so whether or not you are really simulating it is open to question....and you can't simulate everything with a program that is within the system, as it would have to be outside looking down on it. But then, the 'system' in question wouldn't be the whole universe, etc.

Nate Davis said...

The point about astrology has been made to me before. And your response to it is about how I feel; without knowing more, the discussion necessarily includes a lot of hand-waving. Also, astrology writers usually don't actually look at the sky. So, you know.

Kevin Stacey said...

"But if free will is an illusion, mistaken appearance of causeless effects, then for the very same reasons, so is natural selection."

I’m not sure I agree that a determined universe renders natural selection an illusion. We perceive natural selection as a “force” that shapes random variation and “governs” the evolution of life. I agree that if the universe is fully deterministic that such a governing force isn’t necessary. But that doesn’t mean the basic phenomenon we observe--the fact that some phenotypes are more advantageous than others--doesn't exist. It just means that the phenomenon is an effect rather than a cause. Rather than being a “force that shapes,” natural selection is an observable manifestation--an echo--of the underlying machinations of the universe. And as such it would remain a very real and interesting thing to study (as if we had a choice whether to study it or not).

So, as I see it, natural selection is safe from determinism. Free will, on the other hand, has a problem...

Ken Weiss said...

I thought I answered this yesterday but apparently I mis-hit the 'post' button!

I see your point, but perhaps the difference of view is semantic. I think that the idea of natural selection in the sense we have had ever since Darwin (tho' see below), is on the 'selection' part. That implies contesting variation being screened.

In a purely deterministic world, I think that isn't a good way to represent what's happening. I wouldn't say, for example, that nature 'selected' the orbits of the planets based on their size or distance from the sun. A cannonball makes more damage than a bullet for deterministic reasons.

Of course, that doesn't change your point that, in a sense, the fast fox catches the slow rabbit.

In any practical sense the Darwinian model (modified by a proper understanding of chance) is appropriate because even in a totally clockwork universe, we don't know enough to predict everything so, for any practical purpose, selection is as it appears.

(About Darwin: his idea about inheritance was Lamarckian in the sense that your life experience molds your 'genes'-- he didn't have that word--so there is no need for random variation to arise and be tested against the sieve of competition for limited resources. Any organism that got the resources would produce the good genes)