So what's the problem? People live as if they'll never die. You forget that you're human and fragile. You don't notice how much time has already slipped away. You spend time carelessly, as if you have endless amounts of it. But that day you're wasting on someone or something might be your last. You fear everything like the mortal you are, yet you want everything as if you'll live forever.
What, then, is the reason of this? It is that people live as though they would live for ever: you never remember your human frailty; you never notice how much of your time has already gone by: you spend it as though you had an abundant and overflowing store of it, though all the while that day which you devote to some man or to some thing is perhaps your last. You fear everything, like mortals as you are, and yet you desire everything as if you were immortals.