A defect in the minds function. But does not nessercerily affect your intelegence. Saying a mental illness makes you crazy/stupid/funny is like saying an eating disorder makes you fat.
Bill Gates, who is a multi-billionare, invented the personal computer, is very creative and in the top ten smartest men alive suffers from aspergers syndrome, which is infact a mental illness.
von GavinBobJones 4. November 2006