“There is in life only one moment and in eternity only one. It is so brief that it is represented by the fleeting of a luminous mote through the thin ray of sunlight–and it is visible but a fraction of a second. The moments that preceded it have been lived, are forgotten and are without value; the moments that have not been lived have no existence and will have no value except in the moment that each shall be lived. While you are asleep you are dead; and whether you stay dead an hour or a billion years the time to you is the same.” From Twain’s notebook – 1896
An instant is a lifetime and to dwell on the past or fret for the future is to waddle in what does not exist. In the present is where to find the consequence of past moments and potential for future ones.