杏吧原创

Our hopes, loves and very existence are just elaborate functions of a complicated mass of grey tissue. Accepting that can be hard, but neurophilosopher Patricia Churchland tells Graham Lawton that what we know should inspire us, not scare us

You compare revelations in neuroscience with the discoveries that the Earth goes around the sun and that the heart is a pump. What do you think these ideas have in common?
They challenge a whole framework of assumptions about the way things are. For Christians, it was very important that the Earth was at the centre of the universe. Similarly, many people believed that the heart was somehow what made us human. And it turned out it was just a pump made of meat.

I think the same is true about realising that when we鈥檙e conscious, when we make decisions, when we go to sleep, when we get angry, when we鈥檙e fearful, these are just functions of the physical brain. Coming to terms with the neural basis of who we are can be very unnerving. It has been called 鈥渘euroexistentialism鈥�, which really captures the essence of it. We鈥檙e not in the habit of thinking about ourselves that way.

Why is it so difficult for us to see the reality of what we actually are?
Part of the answer has to do with the evolution of nervous systems. Is there any reason for a brain to know about itself? We can get along without knowing, just as we can get along without knowing that the liver is in there filtering out toxins. The wonderful thing, of course, is that science allows us to know.

Are there any implications of neuroscience that you feel unsettled by?
I鈥檇 have to say no. It takes some getting used to, but I鈥檓 not freaked out by it. I certainly understand the ambivalence people have. On one hand, they鈥檙e fascinated because it helps explain their mother鈥檚 Alzheimer鈥檚, but on the other, they think, 鈥楪osh, the love that I feel for my child is really just neural chemistry?鈥� Well, actually, yes, it is. But that doesn鈥檛 bother me.

By and large I find neuroscience liberating because it allows us to see our connections to other biological things, and because it鈥檚 not full of metaphysical junk about preparing your life for the great beyond. Of course it鈥檚 possible we鈥檙e wrong. But it doesn鈥檛 seem very likely, and that lack of likelihood is sufficient for me to not want to organise my life around this possibility. I want to enjoy it now. I don鈥檛 want to make useless and meaningless sacrifices, and I don鈥檛 want to trash this planet because I think a better one awaits me.

鈥淚 want to enjoy life now, and not trash the planet thinking a better one awaits鈥�

You seem to take it for granted that there is resistance to brain science out there. What led you to that conclusion?
For many years I taught philosophy of neuroscience and my students would often say, doesn鈥檛 it freak you out that you鈥檙e just your brain? Doesn鈥檛 that bother you? So we would talk about why it bothered them. I know some people are ambivalent or apprehensive.

You say that some philosophers are resistant to brain science, too. Why is that?
Many philosophers think, hey, we thought we were going to have all the answers, and now you guys are wading in and telling us what knowledge is? I think there鈥檚 fear of a territorial kind, and rightly so.

You accept that we don鈥檛 have satisfying neural explanations for a lot of higher functions, including consciousness, problem-solving, decision-making, sleep and dreaming. Are we really ready to declare that we are our brains?
True, we don鈥檛 have adequate explanations yet, and it鈥檚 important not to overstate where things are. But that鈥檚 where the evidence is pointing. Everything we鈥檙e learning in neuroscience points us in that direction.

You say beliefs in things like the existence of the soul and life after death are challenged by neuroscience. But are they still widely held?
There are probably cultural variations; it may be that in Britain there is less need to challenge these ideas. But I find that here in America, it is important. Lots of people who don鈥檛 necessarily have strong religious views nonetheless have the feeling that maybe after they die, there鈥檚 something else.

It was quite interesting to see the comedian Jon Stewart interviewing Richard Dawkins recently. He said something like, you really don鈥檛 think that after I die anything happens? I just rot? And of course Dawkins said, yes, I really do think that. And I really think that, too.

Even people who have largely come to terms with neuroscience find certain ideas troubling 鈥� particularly free will. Do we have it?
A better question is whether we have self-control, and it鈥檚 very easy to see what the evolutionary rationale of that is. We need to be able to maintain a goal despite distractions. We need to suppress certain kinds of impulses. We do know a little bit about the neurobiology of self-control, and there is no doubt that brains exhibit self-control.

Now, that鈥檚 as good as it gets, in my view. When we need to make a decision about something 鈥� whether to buy a new car, say 鈥� self-control mechanisms work in ways that we understand: we decide not to spend more than we can afford, to go with the more or less practical car. That is what free will is. But if you think that free will is creating the decision, with no causal background, there isn鈥檛 that.

What about the argument that you can follow chains of causality back to the beginning of the universe, so everything is predetermined?
It鈥檚 metaphysical goofiness. The reason I just scratched my foot is because of that causal connection to the big bang? Get real. Part of why we care about free will is because we care about assigning responsibility. Do we need to know about the relation between my scratching my foot and the big bang in order to make wise decisions about when to punish people for their actions? Of course not.

So I shouldn鈥檛 worry that I don鈥檛 have free will?
Here鈥檚 one way to think of it. Suppose your doctor tells you they have found colon cancer. You have to make a decision whether to have surgery. If you thought there was no such thing as free will because it is causality all the way back, you might say, well, it鈥檚 futile, I cannot make a free decision anyhow, I will just sit here and wait. That would be foolish.

If you are crippled by the thought that it is causality all the way back, you have essentially made a decision to make no decisions. That is very unwise. If by thinking that free will is an illusion you believe that it does not matter whether you acquire good habits or bad, hold false beliefs or true, or whether your evaluation of the consequences of an option is accurate or not, then you are highly likely to make a right mess of your life.

Do you see yourself as a cultural warrior?
Not at all. My intent is to say, I鈥檝e made my peace with my brain, but there is a journey to getting there. I understand that journey, and not everybody will want to make it, but I鈥檒l let you know how I got there. And then you can take it or leave it.

So yours is not an evangelical message, you aren鈥檛 seeking converts?
No, I have no intention or desire to shove anything down anybody鈥檚 throat. People are, by and large, smart enough and reasonable enough that they come to a good decision eventually. But it takes time to think about it, to go back and forth. It鈥檚 something that you have to marinate in for a while.

I just want to lay out what it looks like the science is telling us, because I think people want to know. I think it鈥檚 important to accept what seems to be true rather than make stuff up. In general, I think that鈥檚 a good life policy.

Can neuroscience offer a philosophy to live by?
Neuroscience doesn鈥檛 provide a story about how to live a life. But I think that understanding something about the nature of the brain encourages us to be sensible.

Some might say the idea that you are just your brain makes life bleak, unforgiving and ultimately futile. How do you respond to that?
It鈥檚 not at all bleak. I don鈥檛 see how the existence of a god or a soul confers any meaning on my life. How does that work, exactly? Nobody has ever given an adequate answer. My life is meaningful because I have family, meaningful work, because I love to play, I have dogs, I love to dig in the garden. That鈥檚 what makes my life meaningful, and I think that鈥檚 true for most people.

Now, at the end of it, what鈥檚 going to happen? I will die and that鈥檚 it. And I like that idea, in a crazy sort of way.

This article appeared in print under the headline 鈥淎t peace with my brain鈥�