We build on the empirical finding that a human being's mental age is normally distributed around the chronological age. This opposes the frequent societal assumption "mental = chronological" which is known to be false in general but entertained for simplicity due to lack of methodology; hence disregarding that, f.e., people of different chronological ages can be much closer in their mental ages. As a quantitative approach on a scientific basis, we set up a general formula for the probability that two individuals of given ages are mentally within a certain range of years and investigate its implications i.a. by critically analyzing popular assumptions on age and computing statistical expectations within populations.

翻译：我们根据经验发现,一个人的精神年龄通常按时间年龄分布,这与经常出现的社会假设“精神年龄”相悖,一般认为这种假设是假的,但由于缺乏方法而容易简化;因此我们忽视了这一点,即不同时间年龄的人在精神年龄上可能更加接近。作为一个科学的量化方法,我们为两个特定年龄的人在一定范围内智力年龄的概率制定了一般公式,并调查其影响,例如,严格分析民众对年龄的假设和计算人口内部的统计期望。