Seneca · On the shortness of life
Letters 49.4
It was but a moment ago that I saw you off on your journey; and yet this “moment ago” makes up a goodly share of our existence, which is so brief, we should reflect, that it will soon come to an end altogether. In other years time did not seem to me to go so swiftly; now, it seems fast beyond belief, perhaps, because I feel that the finish-line is moving closer to me, or it may be that I have begun to take heed and reckon up my losses.
Seneca, Letters to Lucilius 49.4, translated by Richard Mott Gummere