It is commonly thought that age brings wisdom.

大众普遍认为年龄增长会带来更多智慧。

And this is largely true, it seems – unless you are Japanese. In which case, by the time you are 25, you are likely to be just as wise as your elders, an astonishing new study reveals.

Americans, however, are more conventional and develop deep understanding over time, according to research by the University of Waterloo in Ontario, Canada.

In one of the tests, designed to measure five crucial aspects of reasoning, US citizens' scores improved by 22 percent over 50 years.

But, in the examination scored out of 100, both 25-year-old and 75-year-old Japanese participants had an average quotient of 51 for intergroup wisdom – the idea of understanding society.

With Americans, on the other hand, results from the same tests varied¹ between averages of 45 and 55 between the two age groups.

Also, interpersonal wisdom – the understanding of relationships between individuals – the scores of the 225 US participants climbed from 46 to 50.

In the case of the 186 Japanese people recruited by lead researcher Igor Grossmann, their scores actually dropped slightly from 53 to 52.

The tests also recorded other unexpected results.

Given the US reputation of an individualistic society, you might expect its participants' interpersonal wisdom to be higher than their supposedly more collectivist Japanese counterparts.

Yet the study showed that by 75, the Japanese scored higher in the interpersonal wisdom and Americans, in fact, achieved higher results in the intergroup variety.

Dr Grossman suggested that perhaps, then, you need individual skills when society is collective, and social ones when it is individualistic.

His study, published in Psychological Science and reported in The Economist², recruited Japanese and Americans with a range of different occupations.