An unhappy childhood has long-lasting adverse effects. A new paper by Nattavudh Powdthavee shows that people who reported a high fear of being bullied between the ages of 11 and 15 not only have lower happiness, lower incomes and worse health in adulthood, but also suffer more if they become unemployed. They are less resilient to adverse events.
Now, there could be an endogeneity issue here. If kids pick on kids they sense are vulnerable, then bullying in childhood might be correlated with a lack of resilience in adulthood, without bullying playing a causal role.
But there's another possibility. It could be that bullying weakens individuals' hedonic capital (pdf) - for example by lowering their self-esteem and ability to make friends or trust people - and this increases their psychological vulnerability in later life.
Insofar as this is the case, it adds to a large body of evidence which shows that circumstances in our childhood - or earlier - help determine our success in adulthood. For example, we know that a healthy birthweight, good health (pdf) in childhood, being taught in small classes and having a father who stays in work (pdf) are all associated with better outcomes in later life. And as James Heckman has shown, non-cognitive skills acquired (or not) very early in life matter (pdf) enormously for adult success.
One inference I draw from this is that mere formal equality of opportunity is a harmful myth. By the time an individual is mature enough to stand a chance of being able to take decisions herself, her life chances have already been heavily shaped by circumstances beyond her control. None of us is a "self-made man".
For me, this is one argument for strongly redistributive policies. They help to compensate people for misfortunes beyond their control - such as a disadvantageous upbringing - which blight them in later life.