“I flatter myself,” Hume triumphantly proclaimed, “that I have discovered an argument . . . which, if just, will, with the wise and learned, be an everlasting check to all kinds of superstitious delusion, and consequently, will be useful as long as the world endures.”

Geologist Keith Miller examines the "Cambrian Explosion", a period of rapid evolutionary diversification approximately 575 million years ago, and whether it poses a challenge to evolutionary theory.