Anatomists, until the women had the vote, developed a number of ingenious arguments from the study of the brain to show that men's intellectual capacities must be greater than women's. Each of these arguments in turn was proved to be fallacious, but it always gave place to another from which the same conclusion would follow. It used to be held that the male fetus acquires a soul after six weeks, but the female only after three months. This opinion also has been abandoned since women have had the vote.
Source: Bertrand Russell: Ideas That Have Harmed Mankind，1946.
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