In Zero, Charles Seife presented readers with a thrilling account of the strangest number known to humankind. Now he shows readers how the power of skewed metrics-or "proofiness"- is being used to alter perception in both amusing and dangerous ways. Proofiness is behind such bizarre stories as a mathematical formula for the perfect butt and sprinters who can run faster than the speed of sound. But proofiness also has a dark side: bogus mathematical formulas used to undermine our democracy-subverting our justice system, fixing elections, and swaying public opinion with lies. By doing the real math, Seife elegantly and good-humoredly scrutinizes our growing obsession with metrics while exposing those who misuse them.