What do Bill Gates and Paul McCartney have in common with criminals?

In my last series (Why are almost all criminals men? Part I, Part II, Part III, Part IV), I explain why men are so much more likely to commit violent and property crimes than women. It turns out, however, that there is nothing special about criminals. All men are essentially the same.

For a quarter of a century, criminologists have known about a persistent empirical phenomenon called the “age-crime curve.” In their highly influential 1983 article “Age and Explanation of Crime,” two leading criminologists, Travis Hirschi and Michael R. Gottfredson, claim that the relationship between age and crime is the same across all social and cultural conditions at all times. In every society, for all social groups, for all races and both sexes, at all historical times, the tendency to commit crime and other analogous, risk-taking behavior rapidly increases in early adolescence, peaks in late adolescence and early adulthood, rapidly decreases throughout the 20s and 30s, and levels off during middle age. Although there have been minor variations observed around the “invariant” age-crime curve, the essential shape of the curve for serious interpersonal crimes is widely accepted by criminologists. Crime is essentially a young men’s game.

One of the striking features of the age-crime curve is that it is not limited to crime. In the words of the evolutionary psychologist Geoffrey F. Miller, the same age profile characterizes “every quantifiable human behavior that is public (i.e. perceived by many potential mates) and costly (i.e. not affordable by all sexual competitors).” The relationship between age and productivity among male jazz musicians, male painters, male writers, and male scientists, which might be called the “age-genius curve,” is essentially the same as the age-crime curve. Their productivity -- the expressions of their genius -- quickly peaks in early adulthood, and then just as quickly declines throughout adulthood. The age-genius curve among their female counterparts is much less pronounced and flatter; it does not peak or vary as much as a function of age.

It is not difficult to find personifications of the age-genius curve. Paul McCartney has not written a hit song in years, and now spends much time painting. Bill Gates is now a respectable businessman and philanthropist, and is no longer the computer whiz kid of his earlier years. J. D. Salinger now lives as a total recluse and has not published anything in more than three decades. Orson Welles was mere 26 when he wrote, produced, directed, and starred in Citizen Kane, which many consider to be the greatest movie ever made. (In the words of the singer-songwriter Jill Sobule, in her song “Heroes” (Album: Pink Pearl), “Orson Welles peaked at 25, ballooned before our eyes, and he sold bad wine.”) There are some exceptions. Some artists, writers, and scientists remain productive into their middle and old ages, just as there are a few career criminals who commit crimes all their lives. But, in general, the pattern of youthful productivity holds for most, regardless of what field they happen to be in.

What is the reason behind all of this? Why do criminals usually desist from committing crimes as they age? Why does the productivity of creative geniuses also often fade with age? I’ll address these questions in my next post.