Carl Sagan used to think of astronomy as the ultimate truth. Our ancestors used to think that they were the at the center of everything and everything has been made for them. But should we blame them for thinking so? The Sun, the planets, and all other heavenly bodies do seem to revolve around us, so it is natural to come to such a conclusion.
But, then we discovered the telescope and looked up and saw that actually the planets and asteroids and all revolve around the Sun. The sun must be the center of everything then. The planets, revolve around it, so should the other stars visible during the night. This took our special place in the universe one level down.
But as we developed better space observation techniques, we found out that we live in a galaxy with billions upon billions of stars that do not revolve around the sun. The sun is just a regular star like them and they all revolve around the center of our Milky Way Galaxy. So, the milky way galaxy must be all there is, with billions of stars, planets, nebulae, etc that go around its center (Beware!! There’s a supermassive black hole there). Our special place in the universe just went down one more level!
But later again, Edwin hubble discovered that the andromeda nubula that we see from earth is not really a nubula. But its a whole freaking Galaxy far away from the milky way!!! There are billions upon billions of galaxies and ours is one of them. Nobody revolves around anybody due to its special place in the universe. Everyone is just moving because gravity is telling them to do so. Our special place is now in the trash.
At this scale, it feels like we are just a mere coincidence. Living on a very tiny planet that supports life (possibly the only one that does). If we were to go extinct, no one would ever notice that we existed in the first place. All of us have one thing in common for sure apparently, all of us have been given this one life, ONLY one. So, why be sad and depressed, why not be happy and keep everyone else happy, save the sadness for the next life.