At 19, I read a sentence that re-terraformed my head: "The level of matter in the universe has been constant since the Big Bang."
In all the aeons we have lost nothing, we have gained nothing - not a speck, not a grain, not a breath. The universe is simply a sealed, twisting kaleidoscope that has reordered itself a trillion trillion trillion times over.
Each baby, then, is a unique collision - a cocktail, a remix - of all that has come before: made from molecules of Napoleon and stardust and comets and whale tooth; colloidal mercury and Cleopatra's breath: and with the same darkness that is between the stars between, and inside, our own atoms.
When you know this, you suddenly see the crowded top deck of the bus, in the rain, as a miracle: this collection of people is by way of a starburst constellation. Families are bright, irregular-shaped nebulae. Finding a person you love is like galaxies colliding. We are all peculiar, unrepeatable, perambulating micro-universes - we have never been before and we will never be again. Oh God, the sheer exuberant, unlikely face of our existences. The honour of being alive. They will never be able to make you again. Don't you dare waste a second of it thinking something better will happen when it ends. Don't you dare.