Jean Piaget

Pour water from a short glass into a tall one, and a young child will tell you there is now more to drink - and mean it. That small mistake is a window into how the human mind is built.

Jean Piaget spent sixty years taking children seriously as thinkers. Trained as a naturalist who catalogued molluscs before he had heard a lecture in psychology, he noticed something in a Paris testing lab that everyone else was scoring as failure: children of the same age got the same questions wrong in the same way. Their errors were not gaps. They were evidence of a different, coherent logic - a mind in the act of construction.

Jean Piaget: A Gateway to His Life, Ideas, and Legacy is a clear, human introduction to the man behind the four stages and the water glasses. It follows him from a lakeside boyhood in Neuchâtel to the Geneva laboratory where he turned the oldest question in philosophy - where does knowledge come from? - into something you could set on a table and watch a four-year-old answer.

Inside, you'll discover:

• What Piaget really meant by his famous stages - and why the ages on the nursery-wall chart were always approximate
• The simple, ingenious experiments (conservation, object permanence, the three mountains) that made an invisible mental structure visible
• Why he insisted a wrong answer is not an absence of knowledge but a report from a different and temporarily valid world
• The fair, unflinching reckoning his work demands - the small samples, the tasks that underestimated the young, and Vygotsky's charge that he undervalued the social side of learning
• What has been revised, and what endures: the idea that children build their understanding rather than absorb it

Part of the Pioneers of Human Behaviour series: premium, accessible, carefully researched gateways into the people who changed how we understand the mind. Quotations and key facts are checked against primary texts and trusted scholarship.

Whether you are a student, a teacher, a parent, or simply curious about how a mind comes to know anything at all, this is the honest, illuminating introduction to one of the most influential thinkers in the science of human development.