Why does masculinity seem obvious yet prove impossible to define?What has caused the erosion of men’s power and will progress towards sexual equality continue?How political is the personal?This book explains why both popular and academic commentators have found it impossible to define masculinity. It is because no such thing exists. Re-examining the ideas of thinkers such as Sigmund Freud and Thomas Hobbes, the author shows that modern societies faced the novel problem of explaining how men and women had equal rights, yet led such different lives, and solved it by inventing the concept of masculinity. It concludes that strong forces in modern societies encourage greater sexual equality, and that these are better supported by a politics of equal rights than by encouraging men to personally reform their masculine identity. Mac Innes challenges established ways of thinking about sex, gender and masculinity that underpin not only feminist thought, but the treatment of these issues across the social sciences, philosophy and history.