A: I am insane.
B: I am pure.
C: I am applied.
D: I am sane.
A: C is pure.
B: D is insane.
C: B is applied.
D: C is sane.

You are also given that:

Pure mathematicians tell the truth about their beliefs.
Applied mathematicians lie about their beliefs.
Sane mathematicians beliefs are correct.
Insane mathematicians beliefs are incorrect.

Describe the four mathematicians.

I know you meant D not C so here is my counter argument. If D were right insane, he would believe himself sane and therefore could easily tell himself to be sane truthfully. P.S. my answer is wrong so don't look at it.

Posted by Jon on 2003-04-14 07:29:14