x + y

"This book changed my life in the most beautiful way. Eugenia Cheng doesn't just explain why the way our society conceptualizes gender is all wrong -- she proposes a new way of thinking about -- and beyond -- gender....Stunning."—Rebecca Ramirez, National Public Radio

"On yet another adventure in using the logic of math to address social and emotional issues, author Cheng takes on gender equality...She frames her thinking with relatable examples and anecdotes....Her arguments are both passionate and logical."—Booklist (starred review)

"This is an important topic and an important time to find better ways to have conversations."—New York Times

"A bold and optimistic theory of gender and cooperation, based on the insights of math"—Katy Guest, The Guardian

"Eugenia Cheng is on a mission to change the world for the better, using math.... It's another bold and optimistic thought...if we were ever going to imagine a whole new theory of people, now is as good a time as any to start."—Guardian

"x + y is a book very much designed to change the world."—Times Higher Education

"A carefully developed argument that urges us to discuss character traits without reference to gender."—Kirkus