ABSTRACT
Many aspects of critical thinking (CT) are desirable and would be expected to support rationality, but CT, too, qualifies as another necessary but not sufficient condition for good rational thinking. Despite someone having acquired good CT habits, there is no guarantee that sufficient account has been taken of training other cognitive attributes that are known to be important for sound decision making. So, critical thinkers may still make erroneous judgments. Thus, it appears that critical thinking is "a subspecies of rational thinking". "Rationality" has different specialized meanings in economics, sociology, psychology, evolutionary biology, and political science. Decision making is the engine that drives all behavior in the animal world and ultimately determines survival. Rationality is the dominant characteristic of cognition and is largely responsible for the calibration of diagnosticians' thinking. Rationality comes in two forms: instrumental and epistemic, which are both essential.
