Written by J. A. Bierens de Haan, this book contains a concise yet comprehensive investigation into the topic of animal psychology. This fascinating treatise is based on the idea that all animal behaviour is a result of instinct alone, and that singular experiences accrued during the lifetime of an animal might influence these instincts. Contents include: “The Problem of Animal Psychology”, “The Problem of Animal Instinct”, “Learning the Problem of Animal Intelligence”, “The Problem of Animal Understanding”, “The Problem of Animal Ideation”, “The Problem of the Animal's World”, etcetera. Johannes Abraham Bierens de Haan (1883 - 1958), was a Dutch biologist and ethologist, born in Haarlem in North Holland. Many vintage texts such as this are increasingly hard to come by and expensive, and it is with this in mind that we are republishing this book now, in an affordable, modern, high-quality edition. It comes complete with a specially commissioned new biography of the author.