Lucius Annaeus Seneca (c 4 BC - 65 AD)

https://en.wikipedia.org/wiki/Seneca_the_Younger

De Brevitate Vitæ (On the shortness of life) – Essay expounding that any length of life is sufficient if lived wisely – addressed to Paulinus

https://en.wikipedia.org/wiki/Seneca_the_Younger#Works