- The fact that your lifespan is an infinitesimally tiny fragment in the life of the universe, and that there is, at the very least, a strong possibility that when you die, you disappear completely and forever, and that in five hundred years nobody will remember you and in five billion years the Earth will be boiled into the sun ... it can make everything you do, and everything anyone else does, seem meaningless, trivial to the point of absurdity.
The article goes on to talk about how change always results in loss (but not how change also results in new joy, except as an afterthought) and thinking about one's existence by detaching completely from the universe, to think of its timeline as a whole. Then at the end it says "but all of that's okay because you got to be alive."
What a depressing way to look at the universe. What a negative way to spin the same thing I would say, which is that the meaning of life is to live. But we are not individual motes of meaningless dust in a vast, uncaring universe. We are all connected to everything else, individual threads in a great tapestry, individual drops in a mighty stream. Each of us might be small, but we all matter. And meaning is found in each individual moment that we live.