Alva NoĆ« talks about why we are not our brains

The extended mind is an interesting theory of consciousness and cognition that attempts to reshape the way we look at what it means to be human. Does they mind end at our meaty borders? Can palm-pilots become external modules of the mind? I’m not so sure if there is much about the theory that is explanatorily interesting, but it is fun to think about nonetheless.


Russell on mind and matter

A stone at the top of a hill may start rolling, but it shows no pertinacity in trying to get to the bottom. Any ledge or obstacle will stop it, and it will exhibit no signs of discontent if this happens. It is not attracted by the pleasantness of the valley, as the sheep or cow might be, but propelled by the steepness of the hill at the place where it is. In all this we have characteristic differences between the behaviour of animals and the behaviour of matter as studied by physics.

B. Russell, The Analysis of Mind, p. 14.

I think Russell’s point is important to remember when doing consciousness studies: no matter what your view of ultimate or foundational reality is, there is a prima facie difference between brains that act for reasons and the brute mechanics of dumb matter. This either needs to be explained or explained away, but either way it needs to be accounted for.

The Evolutionary Explanation of Rationality

I take the following argument (word for word) from Steven Stich’s fantastic book The Fragmentation of Reason:

(1)Evolution is caused by natural selection.
(2)Natural selection will choose the best-designed (i.e., that most fitness-enhancing) system available in the gene pool.
(3)Over evolutionary time, a huge and varied set of options will be available for natural selection to choose among, and this set is very likely to include one or more that closely approximate a theoretical optimum.
(4)Systems produced by evolution can be expected to be about as well designed as it is possible to be.
(5)Our inferential system was produced by evolution.

Stephen Stich, The Fragmentation of Reason (Cambridge: MIT Press, 1990), 63.

For context, Stich is attempting to construct an evolutionary explanation of our belief that the human mind is rational (to whatever degree). He critiques every point, but what is most damaging to the case is that it is no way explains why the mind must be rational. There needs to be some ancillary proposition that states something like “Rationality has a monopoly on survival enhancing behavior.” I’m not positive that is a very helpful way to word it (I’m open to suggestions), but the missing premise needs to include something to the effect of survival-enhancing behavior necessitating rational beliefs. Since any missing premise built around that concept is probably wrong (and open to clear counterexample) there can be no evolutionary explanation of rationality (even if our minds evolved by the mechanisms of contemporary evolutionary theory).

Descartes presents the replacement argument to the princess

I’ve been discussing Descartes’ version of the replacement argument with a chap here, and since I can’t find an online copy of the dialogue I’m going to type out the relevant passage from a printout. This is from a book no one will probably ever see again, but I printed off the passage from a friend who stumbled upon it.

Elizabeth: How are they connected?
Descartes: Well, it’s really to do with possibilities. If it is possible for thinking to go on apart form a body then…
E: [Interrupting] But is it possible? That’s the question.
D: All right, I’m coming to that. I did say “if”. If it is possible for thinking, and the body, to exist in separation then…
E: [Impatiently] Yes, yes, then what-does-the-thinking isn’t the body. I can quite see that. But what you’ve got to do is to get rid of the “if”. That is, you’ve got to show it to be possible for thinking to go on apart from a body.
D: Precisely, and that is where what I know and don’t know, comes in.
E: Go on.
D: Well, I know certainly that I am thinking and at the same time I can doubt that I have bodily attributes. So I can perceive the one thing, the thinking, apart from the other. And since this perception is clear and distinct it must be possible for the one thing to exist apart from the other.
E: Just a moment. You said :since this perception is clear and distinct.”
D: Yes.
E: And therefore you really are no more than a thinking thing?
D: Exactly.
E: All right. Well now, isn’t is possible that your perception is clear, but only as far as it goes? And that it doesn’t go far enough for you to know the truth? In other words, isn’t it possible that you really do have bodily properties although your knowledge of yourself doesn’t go beyond your mental properties.
D: No. You must distinguish between clearness and completeness. Certainly there may be things about me which I haven’t clearly perceived. But that doesn’t affect what I have clearly perceived. And, having clearly perceived that I am a thinking thing, I know that I can exist as such. That is, I know that what I am certain of- my intellectual faculty- is enough for me to exist with. And if it is enough for me to exist with, then I really am distinct from anything bodily.
E: So, the principle of your argument is: if I can clearly perceive something to be such-and-such while I cannot clearly perceive it to be so-and-so, then it can exist simply as such-and-such.
D: Yes.

This is a fascinating exchange that, as far as I can tell, has many components of the discussion that has cropped up around Plantinga’s version. More on that as we progress into an analysis of Plantinga’s presentation of the argument.