The following occurred to me on waking from a nap this afternoon: Existentialism can be summed up in just six words consisting of two sentences:
You’re going to die.
Your move.
Chess players, medieval Germany, circa 1305-1340. (Image source: Wikipedia Commons.)
Prometheus Unbound 
Reblogged this on Oxtapus *blueAction.
To me that seems to be a self-refuting definition.
Only if you take death as immanent in the next moment. Death is certain; when you will die is not. Your move.
I was referring to “Your move”
That statement admits
– that we have agency (we can act, ‘your’ move)
– that there is opportunity or space to act (death is in the future, ‘going to die’)
– that there is purpose (‘move’ is directed action)
Placing it implicitly in the context of a chess game just reinforces the interpretation. The chess board is symbolic of an ordered world with clear rules and well defined purpose. It is true the game is a struggle, with many casualties and also ends in death. And yet in that struggle we find such intense meaning(ask any chess player). Furthermore there is always the next game. As a devout Catholic(and chess player) I find your analogy very appealing.