Reason is often thought to be the distinguishing characteristic of our species. While scientists recognize that animals can make inferences based on previous information, humans are unique in that we may be conscious of a great deal of our inferential processes. Furthermore, we have the capacity for imagination or innovative thinking. However, rationality is not without its paradoxes. While it underpins the achievements of science and technology, securing a dominant status for our species, human reasoning is also prone to error. Cognitive biases belie the idea that human thought follows the rules of logic. This has led to the so-called “rationality wars,” which revolve around the question of whether we are rational or irrational, and what “rationality” ultimately means.