Even geniuses change their minds sometimes. Edge (www.edge.org), the influential online intellectual salon, recently asked 150 high-powered thinkers to discuss their most telling missteps and reconsiderations: What have you changed your mind about? The answers are brilliant, eye-opening, fascinating, sometimes shocking, and certain to kick-start countless passionate debates. Steven Pinker on the future of human evolution - Richard Dawkins on the mysteries of courtship - SAM HARRIS on the indifference of Mother Nature - Nassim Nicholas Taleb on the irrelevance of probability - Chris Anderson on the reality of global warming - Alan Alda on the existence of God - Ray Kurzweil on the possibility of extraterrestrial life - Brian Eno on what it means to be a "revolutionary" - Helen Fisher on love, fidelity, and the viability of marriage - Irene Pepperberg on learning from parrots . . . and many others.