Earth-One (also Earth-1) is a name given to two fictional universes. DOC takes us on a joyride.
"Service to others is the rent you pay for your room here on earth-1"
― Muhammad Ali
“Finally, from what we now know about the cosmos, to think that all this was created for just one species among the tens of millions of species who live on one planet circling one of a couple of hundred billion stars that are located in one galaxy among hundreds of billions of galaxies, all of which are in one universe among perhaps an infinite number of universes all nestled within a grand cosmic multiverse, is provincially insular and anthropocentrically blinkered. Which is more likely? That the universe was designed just for us, or that we see the universe as having been designed just for us?”
― Michael Shermer