Mental Darwinism, a new approach to the study of mental phenomena, applies selectionist ideas to problems of mind and behavior. McNamara challenges the instructivist view that memories occur when information from the environment is transferred into the mind. Current experimental evidence confirms the insights of two turn-of-the-century philosophers, William James and Henri Bergson, who originally proposed applying Darwinian principles to mental processes. The view of the mind that emerges from this approach helps us understand why memory evolves as it does and is not always accurate or veridical, how memory is related to personal identity, and how a large number of neuropsychological disorders develop.