The Dawn of Reason; or, Mental Traits in the Lower Animals

The Expression of the Emotions in Man and Animals

The Critique of Pure Reason

Zoölogische Philosophie Of beschouwingen over de Natuurlijke Historie der dieren etc.

Clever Hans (The Horse of Mr. Von Osten) A contribution to experimental animal and human psychology

Was heißt: sich im Denken orientieren?

Animal Life and Intelligence

La simulación en la lucha por la vida

Intelligence in Plants and Animals Being a New Edition of the Author's Privately Issued "Soul and Immortality."

Kant-breviarium: Kant világnézete és életfelfogása

Animal intelligence: Experimental studies

Straußenpolitik