What makes people irrational thinkers?

[polymath257]

Too bad my library is packed away otherwise I would have liked to participate more fully on the book discussion. My question for the physicalists is this. Can a rational person not be a phyicalist? In your world are people in general, allowed to be wrong and have a different metaphysics from physicallism without attributing their beliefs to irrationality, delusion, or malice? And the follow-up to that is has that been the case, in particular, with Hart?

If rational just means 'reasoned' then people can reason themselves into all sorts of positions, using all sorts of different 'frameworks' of understanding to get there. So no, I don't think you're irrational... or any more irrational than anyone else, myself included... you just use a different framework of understanding than many people, ie Aristotle etc, to arrive at your conclusions. And can a rational person not be a physicalist? Again I don't see why not, if all we mean is 'reasoned' then you only need to look at all the different theories on consciousness for example, and/or solipsism etc, to see the diverse places reason can take people. It's always been kind of ironic to me how we can all claim to be using logic, but yet never agree on anything, and this is the main reason why I think... just different frameworks of understanding. Anyway, as to the book/Hart, I'm not reading it, just following the discussion here, so no comment from me on that.

Exactly. Logic *alone* is a very, very weak filter for ideas. At best, it determines if they are internally consistent. It cannot determine if they are actually true.

This is also true of math, by the way.

At some point, it is crucial to have actual observations as an additional filter. Logic and math alone simply are not enough.

Now, the question is whether the *completely logically defensible* position of solipsism is 'rational'. I would say not, but that is because of my metaphysical biases, I guess.