Originally Posted by Carbonfiberboy

Not being a neuroscientist, I don't really know. However how the brain works is what they study, and our view of ourselves is part of that. Have you read Oliver Sacks? If not, you might enjoy him.

Our moralities descend from how we see the world and our place in it. They are all artificial constructs which hopefully aid the human community, though obviously many times they are in conflict with that goal. Social evolution is a scientifically valid concept. It's much faster than the biological form, though not a heck of a lot. It's possible that the two forms interact.

The older we get, the more our bodies change. Some of these changes allow older people to use fewer calories to sustain themselves than younger people use. This may be an adaptation to allow older members of the community to survive longer and thus pass on their valuable experience. The location of water holes is just a small part of it. So no, in my view we do not have a duty to die when we can't "work" any longer. In fact, the whole concept of "work" is a slightly bizarre moral construct, probably foisted upon us by those who wish to profit from it. We have a duty to survive. Our genes cry out the truth of this to us. No one wants to die. We all want to live. This is a good thing for the survival of human communities.

If we can extend the period during which we are useful to society simply by our very survival (grandchildren, anyone? Great grandchildren?), we do good. If we can do this a very low cost to society in terms of medical and other care, so much the better. I hope that is a goal of most of us on this forum, not just our own pleasure in cycling. It's interesting that this pleasure does good for society. Our drives and the morality behind of them are of great interest, apparently even to neuroscientists.