People try to be happy because they intrinsically want to be happy. Not because being happy matters after you're dead -- obviously you're not in a state to be happy after you're dead. At least not in this world.

Why do people want to make a lasting change? Purely for intrinsic reasons? Or is there some hidden assumption like for example that it will make them happy in their later years?

Satisfaction from seeing "fruits of your labor" improve the condition of everyone is also a source of happiness. I don't think it's worse than happiness from having a good family life. I also don't think there's some kind of "altruism" that isn't ultimately just another way of getting happiness - maybe a more intellectual one, out of the feeling of doing something one considers morally good.

> Satisfaction from seeing "fruits of your labor" improve the condition of everyone is also a source of happiness. I don't think it's worse than happiness from having a good family life.

Yet you seemed to want to draw a distinction between happiness and a lasting impact. Though the distinction was perhaps just with the family/local impact.

> I also don't think there's some kind of "altruism" that isn't ultimately just another way of getting happiness - maybe a more intellectual one, out of the feeling of doing something one considers morally good.

Right, but a family-related happiness is less because it's just a result of chemicals (oxycotine?) that are related to survival, a sort of failure mode? You said yourself that it is less fundamental. What is fundamental? And why is your derivation of happiness higher than those who go by the supposed more base instincts of focusing on their family? Because the hormonal causes are harder to pin down and analyse? So what? Something more complex and harder to describe is better?

If you feel happy, I think the distinction of why is unimportant.