Delusions of Gender: How Our Minds, Society, and Neurosexism Create Difference, also known as Delusions of Gender: The Real Science Behind Sex Differences, is a 2010 work of feminist nonfiction by British psychologist and philosopher Dr. Cordelia Fine. Through an intensive but accessible review of neurological and sociological studies, the book debunks the idea that men and women have different brains. Nominated for numerous awards upon its publication, it went on to become a bestseller. Fine is credited with coining the term “neurosexism.”

In Delusions of Gender, Fine gives a comprehensive review of contemporary and historical neuroscience, observing the pervasiveness of sexist discrimination in the field, the real-world consequences of the gender stereotypes that neurosexism helps to uphold, and the difficulty of effecting change. She takes a strong anti-essentialist view of gender, maintaining that socialization, environment, and acculturation are the true sources of gender difference—not biology or physiology.

The book is divided into three parts: “Half-changed World, Half-changed Minds,” on the origins and persistence of gender stereotyping and the way that such stereotyping affects human behavior; “Neurosexism,” on the ways in which sexism has inflected and driven studies of gender difference in the human brain; and “Recycling Gender,” on the self-perpetuation of gender stereotypes, particularly in children.

Fine provides a survey of a wide array of studies, presenting scientific technique (and its abuses) to a lay audience. Throughout, she maintains that the science underlying theories of innate gender difference is fundamentally flawed; she repeatedly debunks those studies that purport to prove such differences, often discovering poor and even implicitly sexist assumptions in their design and execution.

The malleability of human identity is a major theme of the book. While popular discourse would have us believe in the “hardwired” brain—the brain as mechanical device, with innate and unchangeable proclivities programmed in—Fine argues that, in reality, the brain’s functions are more nuanced, more flexible, and less clearly legible than we’re used to assuming. On the basis of numerous studies that demonstrate how people adjust their self-perception, behavior, and capabilities to meet societal gender expectations, Fine maintains that sexist stereotypes are both self-perpetuating and far from inevitable.