Stephan Lewandowsky is an Australian psychologist. He has worked in both the United States and Australia, and is currently based at the University of Bristol, UK, where he is the chair of cognitive psychology at the School of Psychological Science. His research, which originally pertained to computer simulations of people's decision-making processes, recently has focused on the public's understanding of science and why people often embrace beliefs that are sharply at odds with scientific evidence.

The Psychonomic Society is an international scientific society of over 4,500 scientists in the field of experimental psychology. The mission of the Psychonomic Society is to foster the science of cognition through the advancement and communication of basic research in experimental psychology and allied sciences. It is open to international researchers, and almost 40% of members are based outside of North America. Although open to all areas of experimental and cognitive psychology, its members typically study areas such as learning, memory, attention, motivation, perception, categorization, decision making, and psycholinguistics. Its name is taken from the word psychonomics, meaning "the science of the laws of the mind".