It has long been a central conviction of western humanistic thought that reason is the most godlike of human traits, and that it makes us unique among animals. Yet if reason directs what we do, why is human behavior so often violent, irrational and disastrous? In Within Reason , leading neurologist Donald B. Calne investigates the phenomenon of rationality from an astonishingly wide array of scientific, sociological, and philosophical perspectives--and shows that although reason evolved as a crucial tool for human survival, it is an aspect of mind and brain which has no inherent moral or spiritual qualities and one whose relationship to our thoughts and actions may not be as central as we want to believe. Learned, lucid, and always illuminating, Within Reason brings together the latest developments in the science of mind with some of the most enduring questions of Western thought.