The Moir-Jessel Brain Sex Test

The “brain sex” concept put forth by Moir and Jessel is far more troubling to me than the Bem Sex Role Inventory.

Description: The purpose of the Moir-Jessel Brain Sex Test is “to determine whether your brain functions within the normal range for a male or a female.” This test gives two scores of which the participant selects the correct one for their sex. The interpretation of these scores, breaks the male and female scores each into three categories.

  • Males scoring less than 0 are “Extremely Masculine.”
  • Males scoring between 0 and 60 are “Normal Males.”
  • Males scoring greater than 60 are “Feminine Males.”
  • Females scoring less than 50 are “Masculine Female.”
  • Females scoring between 50 to 100 is “Normal Female.”
  • Females scoring greater than 100 is “Extremely Feminine.”

Anne Lawrence states: “The book BRAIN SEX, from which the test is derived, is a sloppy piece of pop science, full of oversimplifications, unsupported inferences, and speculations presented as though they were facts.” She adds, “The test has not been validated by actual samples of male and female subjects… [T]he test has never been validated with a sample of transsexuals, either.”

I agree about the lack of scientific validity in this extremely controversial book. I would also add that science can be used, or misused, for social purposes. Valid observations can be used to draw absurd conclusions, like the concept of “social Darwinism” put forth by racists and proponents of eugenics.

Moir and Jessel’s Brain Sex is to sexism what Murray and Herrnstein’s The Bell Curve is to racism: a veneer of scientific methodology laid over an agenda that is sexist at its very core. I find the fact that this book is warmly embraced by many transgender women to be a highly troubling commentary on our community’s attitude toward gender stereotypes.

To argue that social inequalities between the sexes is based on brain structure is simply misogyny draped in a labcoat.


Brain Sex (2015 edition)

Gender tests