Philip Johnson-Laird, studies how people infer and deduce the possibility and probability of something happening. He has developed computer programs which quantify the validity of certain deductions, paving the way toward greater understanding of deductive reasoning and thinking that challenge the idea that people have the laws of logic and probability in their heads. Johnson-Lairds book Mental Models: Toward a Cognitive Science of Language, Inference, and Consciousness unifies theories of comprehension, inference, and consciousness. He also studies emotions and cognition. Individuals suffering from psychological illnesses, such as depression or anxiety, in fact reason better than healthy individuals but only about topics concerning their illnesses. An avid composer and jazz pianist, he also studies and teaches the psychology of music. Johnson-Laird is a recipient of the Association for Psychological Science (APS) William James Fellow Award for his lifetime of significant intellectual achievements to the basic science of psychology.