Thomistic thought is anything but dualistic.  Mind is capable of supreme evil because human reason is unfallen in its desire for God and Truth.  You want a summa of The Summa in in a thousand character post?  I'm not a competent student of the Great Doctor's systematic theology in any case.  Sorry, I've read at Aquinas'  Summa Theologica a little, nothing more. 

Darwin admitted, just like the evolutionist JoeErwin below, he doubted there was a creator.  Darwin described himself as a materialist in his private dairies.  The whole structure of the Christian Weltanschauung wobbles and collapses if one species arises out of another, if all species arise out of the deterministic forces of natural selection.  Natural selection, i.e. the survival of the fittest, ordains and determines 'creation' not the God of the bible.