Below is an excerpt of comments from an astute reader of my book, The Meaning of Life: Religious, Philosophical, Transhumanist, and Scientific Perspectives:

The scope of the universe is too large for one human life to have an impactful upon it … The story of life in general, however, is big enough to have meaning in the universe. And our role in the story of life could actually be quite large. Even if individually a life were not very important, we’ve evolved to feel pleasure at the scale we can affect life, so our lives can still feel quite meaningful … The big freeze or the big crunch are still possibilities for universal death within this universe, but maybe … dark energy, dark matter, or something else altogether unknown can be manipulated in such a way as to balance things for survival. Until we can do that, that is a goal which gives meaning to life. We may not be able to answer any ultimate questions now of why the universe and life exist, but maybe someone will be able to someday. It is our job to do what we can to get to that. Survival and scientific progress are prerequisites along that path. Just as Renaissance people (to take one example) could be said to have found meaning in supporting a society that lead the growth of the scientific method, which helped us get this far, we can find meaning today by doing our job to support a society laying the groundwork for future knowledge explorers too.

I think the reader has it about right. The only way our individual lives have objective meaning is if they are part of something larger. We hope then that we are links in a golden chain leading onward and upward toward higher levels of being and consciousness. The effort we exert as we travel this path provides the meaning to our lives as we live them. And if our descendents, in whatever form they take, live more meaningful lives as a result of our efforts, then we will have been successful. Hopefully there will be no end to this progressive, cosmic evolution. Walt Whitman put the point poetically: