The story of the lie detector takes us straight into the dark recesses of the American soul. It also leads us on a noir journey through some of the most storied episodes in American history. That is because the device we take for granted as an indicator of guilt or innocence actually tells us more about our beliefs than about our deeds. The machine does not measure deception so much as feelings of guilt or shame. As Ken Alder reveals in his fascinating and disturbing account, the history of the lie detector exposes fundamental truths about our culture: why we long to know the secret thoughts of our fellow citizens; why we believe in popular science; and why America embraced the culture of "truthiness." For centuries, people searched in vain for a way to unmask liars, seeking clues in blushing cheeks, shifty eyes, and curling toes.
