Can Fish Count?

Bertrand Russell regarded the realization that two apples and two days can share the same abstract idea as one of humanity's great intellectual achievements. This book asks where that idea comes from, given that many creatures seem to have a built-in feel for quantity. Cognitive psychologist Brian Butterworth examines the evidence from the animal world. Bees can tally trees and fence posts, and guppies can judge which group of fish is larger, and these creatures learn none of it from teachers.

Butterworth uses these animal cases to probe the old question of where numbers come from. He also shows how studying other species can sharpen our understanding of human arithmetic. The result is a tour that moves from the natural world into the workings of the human mind.

Butterworth is also the author of The Mathematical Brain.