Thursday, December 19, 2002

Genes build our brains, but then our brains take over

This is a suggestion used to refute the idea that every choice we make is an attempt to maximise the survival chances of our genes.

Indeed, Dawkins uses something like this argument in the last paragraph of the second edition of The Selfish Gene (the endnotes to Chapter 11). He says 'We, that is our brains, are separate and independent enough from our genes to rebel against them'.

But he doesn't explain how our brains became independent of the genes that built them.

But an explanation is needed.

If Dawkins is suggesting that our brains are independent, he needs to give an explanation of the mechanism of change that took our brains from being devices that maximised the survival chances of our genes into 'free-willed' brains that could stop doing what they're told to do and start doing something else.

Dawkins accepts that we are born as survival machines - ie the brain at birth will only make decisions that will maximise the survival chances of our genes. But somehow by adulthood, it's 'free'. He also accepts that if you go back far enough, we had ancestors whose brains were not capable of being independent from their genes. Also, he says that we alone can overcome the tyranny, so presumably its just the human brain that has this independence. No other animal, no other evolutionary creation.

So how did the human brain alone achieve this independence? What would motivate our brains to desire any other outcome?

I think it comes down to an argument of 'can i learn a desire that isn't going to maximise the survival chances of my genes'. If i can, or I can be taught such a desire, then possibly my brain can be free of its genetic programming.

But is this a 'level of programming' that can be altered in our minds?

Here's one way to think about this problem:

A baby is born. It pops out of the womb, opens its mouth, takes a deep breath… and screams at the top of its lungs.

But how does it know whether to scream... or to give a gurgly smile?

Clearly it’s too early for our baby to have learnt anything from its doting parents. It must, therefore, be responding to some automatic, ‘pre-program’ present in its brain before it was born. (ie the first decision is 100% nature.)

It’s still making a decision; responding to the light, the temperature, the size of the nurse… but the criteria it uses to judge these factors must already be present in its brain - it’s had no time to learn

Thereafter, learning begins. The baby builds up experiences of the world, and these experiences have a profound affect on the choices it then makes.

What the baby learns is “What reaction did I get to my first decision?” If the scream achieved a “good” result, the chances are that the baby will repeat the scream. And hence 'nurture' begins to affect the choices made by the baby.

But here's the crucial point:

What decides whether that first result was “good”?

Obviously, if the mother gave the baby something to eat, it's a good result for the baby’s first decision.

But who taught the baby that eating is good... ?

Clearly, it already knew that. Silly point, but crucial: because, although the baby has learned something about its environment, it's only learned what it has to do to satisfy its preprogrammed desires.


And if you follow this reasoning through, that's all it ever can learn. It can only ever learn what's the best way of getting the things that it's pre-programmed to want.

Third decision, fourth decision… last decision before you die… You can only ever build on past experiences, you can only ever judge an experience on a combination of pre-programmed criteria and personal experiences that have themselves only ever been judged on the basis of pre-programmed criteria.

However much you try, you can't alter a baby's primary goals.

- you can teach it that screaming isn't the best way to get what it wants, but you can't change what it wants.

“Nurture” is just a way of working out how to get what we want from the environment. That’s how nurture affects us. And it’s the only way nurture affects us.




So how does the confusion arise in the minds of the parents? Why do parents think they can mould the behaviour of a child so much?

A parent wants a smiling baby not a screaming baby.

But the parent can’t just tell the baby to smile. The parent has to learn what to do to get the baby to smile. So who’s teaching whom? In fact, it’s the baby that’s teaching the parent; the mother modifies her own behaviour to find what it is that the baby is pre-programmed to smile about.

And then, a bit later, when the baby learns that the mother is the source of nice things, it starts to learn how to modify its own behaviour in order to modify the behaviour of its mother. It learns that if it moves its mouth in a particular way - and says ‘mama’ - it gets good food and lots of attention.

If mummy says to her child 'Eat this broccoli, it's good for you', the child will almost certainly give it a try. And then it will find out that it hates the broccoli and it will spit it out again. The child’s pre-program has said 'no way - not enough fat and sugar in that - scream like hell and you'll get some ice-cream like you did last time'.

But although the child might get ice-cream that time, Mummy will start to apply some subtle pressure. And one day she'll say 'If you don't eat this broccoli, you wont get any ice cream at all'. And the child will learn that sometimes you’ve got to suffer some short-term pain in order to get the long term pleasure of the ice-cream. And it will eat the broccoli.

The beautiful scene of a mother teaching her baby is just two machines trying to manipulate each other for the benefit of their genes.



Next: href="http://consciousrobots.blogspot.com/2002/12/couldnt-free-will-have-evolved.html">Couldn't Free will have evolved?



2 comments:

Anonymous said...

I must say that i'm impressed with your arguement. Your logic is brutal and it is difficult to find fault with it (at least in my opinion).
I'm wondering what you think of the person who decides to not have children, as they'd be miserable raising them, but continues to have sex..have they exercised free will in rebelling against their genes?

Anonymous said...

We can indeed free ourselves from our genes. We could free ourselves from our genes by taking a "happy pill" and lying on a "happy bed" with electrodes stuck to our heads. I remember reading that somewhere recently...