I happened across a poem by a minister named Richard Lawrence, part of which reads:
Let no man seek his own,
But every man another’s wealth;
And you’ll be richer than you know,
It will contribute to your health.
The difficulty of living up to this advice is that, if every man is seeking another’s wealth, ultimately for some people to succeed, others have to get wealthy. But then those people are violating the dictum.
This is a generalized problem with altruism: if people are supposed to make sacrifices to others, then the only way for some people to succeed is if others are benefiting by the sacrifices. With sacrifice, some people are losing, and others are gaining at others’ expense.
The final two lines indicate that altruism is in fact good for the one seeking another’s well-being. It can indeed be the case that seeking somebody else’s wealth is self-interested. For example, I want my wife to gain a lot of wealth, and the same goes for all my family and friends, and indeed for all decent people. The problem for altruism is that, in a society of voluntary exchange, I promote the wealth of others in seeking my own wealth. In a free society, one person’s gain is another person’s gain. But that’s not altruism; it’s mutually-beneficial cooperation.
The corrective, then, would read:
Let all men seek their own,
And in exchange another’s wealth;
And you’ll be richer than you know,
It will contribute to your health.
It will contribute to your health and every other aspect of your life.