Folks sometimes ask me why I care about what happens to humanity in the far distant future. I don't even have children, so what do I care about posterity?
First let me address the idea that being childfree renders me less mindful of the future. The children of my siblings are as genetically related to me as my own grandchildren would have been if I had had any. In the vast scheme of things, this one generation difference is inconsequential. Even if my siblings didn't have offspring, I have enough relatives with shared genes to have a genetic stake in the future of my genus, assuming that this matters.
Secondly, I expect to upload into a computer when my meat body gives out and to live on as a machine for a very, very long time. I would like the environment and society to be pleasant and to support the advanced technology that I will need to occupy better and better machine forms.
Thirdly, if my robot plan does not pan out (and even if it does and my roobotic self wears out), I expect to be resurrected at the end of time, and I don't want to have to explain to folks who came after me why my generation was so shortsighted, selfish and douchey.