Emile-Auguste Chartier (1858-1951) was a French professor of philosophy among whose students were Raymond Aron and Simone Weil. Chartier's sunny disposition, however, did not rub off on the brooding Weil. Under the pseudonym 'Alain,' Chartier published thousands of two-page essays in newspapers.
Speaking of the Stoics, Alain writes,
One of their arguments which I have always found good, and which has been useful to me more than once, is their concept of the past and the future. "We have only the present to bear," they said. "Neither the past not the future can harm us, since the one no longer exists and the other does not yet exist."
[. . .]
. . . keep your mind on the present; keep your mind on your life, which moves onward from minute to minute; one minute follows another; it is therefore possible to live as you are living, since you are alive. But the future terrifies me, you say. That is something you know nothing about. What happens is never what we expected; and as for your present suffering, you may be sure that it will diminish precisely because it is so intense. Everything changes, everything passes away. This maxim has often saddened us; the very least it can do is console us once in a while. (Alain on Happiness, Frederick Ungar 1973, trs. R. D. and J. E. Cottrell, pp. 144-145)
The literary merit of Alain's writing is in evidence in the concluding sentence. My only quibble is with the typically Gallic exaggeration: what happens is never what we expected? Ah, the French love of the the universal quantifier!