To: Foo W.
From: Geoffrey Klempner
Subject: How do you know that the author of these words has a mind?
Date: 9 August 2007 11:48

Dear Foo W.,

Thank you for your email of 1 August, with your second essay for the Possible World Machine, in response to the question, 'How do you know that the author of these words has a mind?'

In your essay, you state that you are approaching this question from a mind-body dualist standpoint. Your reason for holding dualism is that 'if monism is true, all our actions and thoughts are merely by-products of the physical states in our brain which then makes us nothing special as individuals but a group of similar human 'robots' that have no free will...'.

Not all material monists would embrace the view that there is no essential difference between a human being and an artificial intelligence (the intelligent 'robot' or 'android' of science fiction) although some do.

Those that do embrace this view - the AI theorists - argue that the human mind is nothing more than a 'program' running on 'wetware' (viewing the brain as a structure capable of running programs, like computer 'hardware'). However, there are strong arguments on the other side that we understand too little about how the brain works, to the extent that it may turn out that there is no 'program' that could be written for a human mind, even in principle. Would this position be so objectionable to you?

I suspect that you would still find the anti-AI non-reductive materialist view objectionable because what it accepts is that human beings are just part of the natural order, that everything we do is capable, in principle, of being understood in terms of natural laws and processes.

However, the main point of this essay question is not to debate the question of materialism but rather to investigate the problem of 'other minds'.

You suggest the following analogy: 'I cannot say a person is rich upon seeing him buying a car nor confirm that he is happy when he is laughing.'

There are two ways of understanding this. In one way, the analogy is correct, but in another way it is incorrect.

You see your friend go into a Bentley dealership and drive out with a brand new Bentley. You are amazed. You never suspected that he could afford a Bentley. When you tell him this, he laughs. 'Didn't you know, I have a new job, delivering Bentleys!'

Another friend phones you up to tell you how unhappy she is feeling, 'But I saw you laughing at the party yesterday!' 'I was just pretending, because my ex-boyfriend was there.'

Both examples show how we can be deceived by appearances. They also show how we can discover that we have been deceived. In this sense, we can talk of knowing how another person is feeling, just as we can talk of knowing whether someone is rich or poor. Sometimes it can be very difficult to find out. (Everyone thinks I am poor but in fact I have a million stashed away in my Swiss bank account.) But that just shows that the two cases are ultimately similar.

However, if you are a dualist, another possibility suggests itself. Your 'friend' does not have any feelings or consciousness AT ALL. He is an example of what materialists believe, that a human being is just physical, a part of nature. As a dualist, you know that you are not like your friend, because you know that you have mind/ soul, while your friend is a mere 'zombie'.

In that case, it seems that you are faced with an insoluble problem. There could not be, in principle, any such thing as 'finding out' that your friend has a mind/ soul, or finding out that your friend does not have a mind/ soul, because by hypothesis his behaviour and physical state will be exactly the same in both cases.

Hence, the point of the question.

There is another possibility. You could go back to the theory held by Descartes and reject the view of modern-day dualists who accept the zombie hypothesis. On the Cartesian view, the soul is what makes the human body 'go'. Take out the soul and the body could not think or talk, because the soul is what makes it possible to do these things. That is the difference, Descartes believed, between humans and animals.

I don't know what you would think about that idea. It is consistent with what you say about our appreciation of art.

In that case, there is the clearest evidence that the author of these words has a mind/ soul, because, according to Descartes, an entity which lacked a mind or soul would be incapable of writing anything, let alone expressing a philosophical question.

All the best,

Geoffrey