The phrase is often extended to explicitly mention the possibility of imminent death, as in "Seize the day, for tomorrow you may die."
Along the same theme, and evoking some of the same imagery as the poem, is the expression "Eat, drink, and be merry, for tomorrow we die", which derives from Biblical verses (such as Isaiah 22:13), and which occurs many times in modern English-language popular culture.
Related but distinct is the expression memento mori, "remember that you are mortal"; indeed, memento mori is often used with some of the sense of carpe diem. However, two major elements of memento mori are humility and repentance, neither of which figures prominently in the concept of carpe diem.
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