The advice is familiar: remember that your days are numbered, and you will spend them more wisely. The earliest source we can find is Psalm 90, whose date is uncertain but which was in the Greek Septuagint by the 2nd c. BCE, so the idea is more than 2,100 years old. It kept coming back, in Seneca’s Moral Letters c. 64 CE, Marcus Aurelius’s Meditations c. 175, The Imitation of Christ in 1427 and Oliver Burkeman’s Four Thousand Weeks in 2021. One book on this page, Spinoza’s Ethics of 1677, argues against it.
Older hints exist: the Egyptian Harper’s Songs and Gilgamesh, from the 2nd millennium BCE, which we have not read and which are reported to use mortality to urge enjoyment, and Plato’s Phaedo, c. 380 BCE, on philosophy as practice for dying, which is about the soul’s separation from the body. Neither says that counting your days makes you live wisely, and Psalm 90:12 is the earliest place we can find that does.
Seneca credits Epicurus by name, “Epicurus will oblige me with these words”, for “Think on death”, and keeps death in view to judge his own conduct. The gain he stresses is freedom.
“Epicurus will oblige me with these words: ‘Think on death,’”
Full text read.
Seneca, Moral Letters, Letter 26, tr. Richard Mott Gummere (1917).
Epictetus says to keep death “daily before your eyes”, and “you will never entertain an abject thought, nor too eagerly covet anything”. He credits no one that we can find.
“Let death and exile, and all other things which appear terrible, be daily before your eyes, but death chiefly; and you will never entertain an abject thought, nor too eagerly covet anything.”
Full text read.
Epictetus, Enchiridion, tr. Thomas Wentworth Higginson (1865).
Marcus writes that you may “depart from life this very moment” and should “regulate every act and thought accordingly”, the claim in his own words. He credits no one.
“Since it is possible that thou mayest depart from life this very moment, regulate every act and thought accordingly.”
Full text read.
Marcus Aurelius, Meditations, tr. George Long (1862).
Thomas says that thinking on death more often than on length of life would make you “strive more earnestly to improve”. He credits no one; Moses and David are named for other points.
“If thou thoughtest upon thy death more often than how long thy life should be, thou wouldest doubtless strive more earnestly to improve.”
Full text read.
Thomas à Kempis, The Imitation of Christ (1.21), tr. William Benham (1909).
Montaigne quotes Horace for treating each day as your last, “Think each day when past is thy last”, and adds his own gain: “The premeditation of death is the premeditation of liberty”.
“The premeditation of death is the premeditation of liberty; he who has learned to die has unlearned to serve.”
Full text read.
Michel de Montaigne, Essays, ‘That to study philosophy is to learn to die’ (1.19), tr. Charles Cotton (ed. W. C. Hazlitt) (1877).
Spinoza holds the opposite: “A free man thinks of death least of all things”, and his wisdom is “a meditation not of death but of life”. He credits no one.
“A free man thinks of death least of all things; and his wisdom is a meditation not of death but of life.”
Full text read.
Baruch Spinoza, Ethics, Part IV, Prop. 67, tr. R. H. M. Elwes.
On his own site, Burkeman calls confronting our finitude “the key to a fulfilling and meaningfully productive life”. He credits no one there for the idea.
“Confronting our radical finitude – and how little control we really have – is the key to a fulfilling and meaningfully productive life.”
Author’s own words, from oliverburkeman.com. Oliver Burkeman, Four Thousand Weeks (2021).
This book is still in copyright, so we read the author’s own words about it, not the book.
How this page was made. AI agents did the reading. Each link was judged by two readers from different AI models, working blind; a third settled their splits (7 of 7 links on this page needed no tiebreak). Every quote was checked word for word against its source. “Full text read” means the agents read the book itself; “Author’s own words” means the author’s free writing elsewhere; “Secondhand” means a free summary or article about the book.