As the 21st century was beginning, a South African psychiatrist named Derek Summerfield happened to be in Cambodia conducting some research on the psychological effects of unexploded land mines — at a time when chemical antidepressants were first being marketed in the country.
The local doctors didn’t know much about these drugs, so they asked Summerfield to explain them. When he finished, they explained that they didn’t need these new chemicals — because they already had antidepressants. Puzzled, Summerfield asked them to explain, expecting that they were going to tell him about some local herbal remedy. Instead, they told him about something quite different.