Having children is negatively related to subjective well-being. Conditioning on individual characteristics shows that the effect of parenthood on well-being is positive and significant only for widowers, older and highly educated individuals…On the basis of a purely economic approach, the optimal number of children for a rational agent is zero.This partly corroborates evidence from the UK (pdf), which shows that children increase the well-being only of married couples and widowers, but reduce the well-being of single or separated parents.
However, the reason for this is rather mundane. Children make (many) people less happy only because they are expensive. Mr Stanca finds that children improve people’s satisfaction with non-financial aspects of their life, but worsen their financial happiness. This corroborates some other evidence (hat-tip).
Even so, this raises questions. Why do people not eventually adapt to having children, with the result that their happiness is unaffected by them? If having children reduces well-being for so many people, is this a failure of rationality? If so, why? Is there just a problem of self-control here, or the power of the desire to conform, or some other bias? If it's rational for (many) people not to have children, why does such a choice often bring with it huge stigma?
And if it is irrational to have children, why should we respect the rights of parents over those children - for example, their right to give them a religious education?