My argument for atheism +

[Belacqua]

My argument for why I don't have delusional thoughts.

Exhibit 1. - Rational mind

The end

What would prohibit an objectively irrational mind from positing the same argument?

I think it might be irrational to assert that you're rational.... And not just you -- I mean everybody.

The idea that we consist of a rational mind trapped in a meat-body is a holdover from religion. We aren't that. We are a body that thinks due to electrochemical events in a meat-brain. The thoughts are affected by hormones and other internal influences, and who knows what other kinds of forces.

There seems to be evidence that toxoplasmosis, something you pick up from cat poo, changes our taste in clothing, for example. And the way you sit in your chair affects your mood, which affects the way you think, which affects the conclusions you reach about things. 

So anyone who claims he's rational is right some of the time, partly.

The idea that just because I think I'm a rational being means I can have confidence about my thoughts -- that's irrational.