Being Taught Not to Lie Key to Bigger Income Says Japanese Study
By wchung | 19 May, 2026

Princess Aiko, then aged 3, plays with her father Crown Prince Naruhito and mother Crown Princess Masako in the garden of Tokyo's Togu Palace, their residence, in November of 2004.

The ethical lessons that parents teach their children have a big impact on their adult incomes, according to a Kobe University study released Friday.

In terms of impact on later income, the most important lesson that parents can impart is, “Don’t lie,” according to an online survey conducted in February by Kobe University professor Kazuo Nishimura. His research team received 15,949 responses to a poll of 90,000 men and women in Japan aged 18 and over who had registered at a research firm.

Respondents who recall being told by their parents not to lie earned an average of ¥500,000 ($5,034) more per year than those who don’t recall being taught that lesson in childhood. The average annual income of those who recall being taught that lesson was ¥4.5 million ($45,300) while those who don’t earned about 4 million yen ($4,027).

Other childhood lessons also have an impact on adult incomes. Those who remember being told to “be kind to others,” “obey the rules” or “study hard” earned ¥150,000 ($1,510) to ¥290,000 ($2,919) more on average than those who don’t.

The biggest payoff went to those who remember all four injunctions — an average of ¥860,000 ($8,658) more than those who don’t recall being taught any of them.

But not all the rules that some parents like to drum into their kids improve their earning potential in later life. Those who recall being taught to “say thank you” or “listen to your parents” showed no meaningful income advantage than those who don’t. Some lessons may even be counter-productive from the standpoint of earning potential. Those who recall being taught to “say hello to others” make ¥130,000 ($1,309) less than those who don’t.

Yet Nishimura concludes in his study that the most important factor is whether a person remembers being disciplined as a child to “observe these manners”.