Why are men so much more likely to be interested in trains than women? I believe this to be a question of profound importance. It has implications for the debate about whether behavioural gender differences are inborn or learned. And implications for our understanding of male thinking.

When at a dinner party did you ever hear an intense conversation between two women about railway timetables? How many teenage girls have you ever noticed among groups of trainspotters? Do small girls ask for a train set as a birthday present? Doesn’t this stark disparity between genders on a matter which touches equally...