The 1950s were not as prudish as they seemed on the surface, says economist Andrew Francis.
The rise in risky, non-traditional sexual relations that marked the swinging '60s actually began as much as a decade earlier, during the conformist '50s, suggests an analysis recently published by the Archives of Sexual Behavior.
"It's a common assumption that the sexual revolution began with the permissive attitudes of the 1960s and the development of contraceptives like the birth control pill," notes Emory University economist Andrew Francis, who conducted the analysis. "The evidence, however, strongly indicates that the widespread use of penicillin, leading to a rapid decline in syphilis during the 1950s, is what launched the modern sexual era."
As penicillin drove down the cost of having risky sex, the population started having more of it, Francis says, comparing the phenomena to the economic law of demand: When the cost of a good falls, people buy more of the good.
"People don't generally think of sexual behavior in economic terms," he says, "but it's important to do so because sexual behavior, just like other behaviors, responds to incentives."
Syphilis reached its peak in the United States in 1939, when it killed 20,000 people. "It was the AIDS of the late 1930s and early 1940s," Francis says. "Fear of catching syphilis and dying of it loomed large."