PARIS, July 9: Creative genius and crime express themselves early in men but both are turned off almost like a tap if a man gets married and has children, a study says.

Satoshi Kanazawa, a psychologist at the University of Canterbury in New Zealand, compiled a database of the biographies of 280 great scientists, noting their age at the time when they made their greatest work.

The data remarkably concur with the brutal observation made by Albert Einstein, who wrote in 1942: “A person who has not made his great contribution to science before the age of 30 will never do so.”

“Scientific productivity indeed fades with age,” Kanazawa says. “Two-thirds (of all scientists) will have made their most significant contributions before their midthirties.”

But, regardless of age, the great minds who married virtually kissed goodbye to making any further glorious additions to their CV. Within five years of making their nuptial vows, nearly a quarter of married scientists had made their last significant contribution to history’s Hall of Fame.

“Scientists rather quickly desist (from their careers) after their marriage, while unmarried scientists continue to make great scientific contributions later in their lives,” says Kanazawa.

The energy of youth and the dampening effect of marriage, he adds, are also remarkably similar among geniuses in music, painting and writing, as well as in criminal activity.

Previous studies have documented that delinquents are overwhelmingly male, and usually start out on the road to crime in their teens.

But those who marry well subsequently stop committing crime, whereas criminals at the same age who remain unmarried tend to continue their unlawful careers.

After a man settles down, the testosterone level falls, as does his creative output, Kanazawa theorises. The study appears in the August issue of the Journal of Research in Personality, published by the Elsevier group. The British weekly New Scientist reports on it in its upcoming issue on Saturday.—AFP