Myths are more than stories. Late last century, some psychologists used mythology as a lens into our psyches. Influenced by Carl Jung’s theories of the collective unconscious, they believed that archetypal characters and motifs recurred in cultures all around the world, and were also present in the minds of people who had no memory of reading them.

In this framework, the man who grew from feuding with his siblings to butting heads with colleagues was drawing fuel from Ares, the Greek god of war; the woman who had a prosaic desk job but measured her life in foreign discoveries and romances was mimicking the adventurer Hermes. The analysts argued that understanding the archetypes people had subconsciously chosen to emulate could help make sense of their life choices.

The pantheon of myt...