In addition to many other titles, the company publishes books on the "right" way to be in a (heterosexual) marriage. Many of these books argue that natural selection leads to men that are "naturally inclined" toward aggression and sexual selfishness.
The British sexologist Havelock Ellis writes that violence in marriage is "natural," and explains that a husband takes “a certain pleasure in manifesting his power over a woman by inflicting pain upon her.”