The major purpose of this paper is to first argue that our thinking in general is adapted to cultural and socio-political environment. The argument will be helped by the connectionist approach that emphasizes learning and therefore nature and nurture interaction. Second, it argues that since most of our thinking or reasoning is cultural product, our evaluation of modes of thinking, too, is influenced by our familiar ways of thinking/reasoning. Third, it delineates fallibility of our cognitive processes themselves and describes some of known cognitive errors in reasoning. Finally, it discusses ways in which critical thinking may be enhanced.