Riniolo begins by reviewing the hallmarks of critical thinking related to the evaluation of claims, such as the use of the double-blind procedure and the law of parsimony. He then provides an evolutionary framework and empirical supporting evidence from cognitive psychology to explain why being inconsistent in the use of critical thinking is part of our evolutionary heritage. Each of us possesses cognitive biases that make us prone to maintaining our current beliefs (both true and false). He concludes by focusing on a wide range of claims—environmental, political, economic, multicultural—to illustrate how in certain contexts we all are tempted to abandon critical thinking.