Sitting on the porch listening to the rain slap the next-door maple's leaves, it occurred to me that too much brevity might not work very well, even if it worked perfectly -- perfectly! -- well.
The brevity that crossed my mind -- the one-liner that simply said it all -- was this:
This is it.
No discussion, no improvement, no holy-roller adjectives or adverbs, no snarling certainties or uncertainties, no deeeeeep Buddhist meaning. Just easy-peasy and complete. Past, present and future go begging and yet prove the point:
This ... is ... it.