For evolutionary biologists, the concept of chance has always played a significant role in the formation of evolutionary theory. As far back as Greek antiquity, chance and "luck" were key factors in understanding the natural world. Chance is not just an important concept; it is an entire way of thinking about nature. And as Curtis Johnson shows, it is also one of the key ideas that separates Charles Darwin from other systematic biologists of his time. Studying the concept of chance in Darwin's writing reveals core ideas in his theory of evolution, as well as his reflections on design,...