We are the Glue
We are neither the body nor the brain. We are the glue that holds the neuroglia, platelets and assorted subchondral osseous tissues from oozing into the vacuous void of the universe, a pink mist of a translucent and truculent goo, just some humanoid cell droppings for an alien spacecraft to clean off his windscreen. I imagine the aliens would have a wash button on the dash that sprays a special windscreen cleaning solution to clean this unmentionable mixture off their shiny spacecraft windscreen.
The glue is not a physical or mental thing, it’s more of an attitude, like the childhood insult about 'I am rubber and you are glue'. Glue is the thing that bonds us together. And by bond, I don’t mean those financial instruments we use to invest that work counter to equities, or that secret agent who drinks things that are shaken and not stirred, I mean those things that help us to hold it all together. For when we choose to give up and no longer hold ourselves together, we might just dissolve into a truculent goo that drifts into space and plops onto the windscreen of a passing alien spaceship and nobody wants that to happen, at least I don’t.