Somehow, it was always expected, always certain, along with taxes.
Now, stripped of the usual diversions and evasions of life, the realization begins to dawn: no matter how healthily you eat, how much you deny your sedentary desires in the name of fitness, no matter how many sacrifices you make to the great God of longevity, you are going to die.
No matter how nobly one might have lived, however much courage one had shown in battle, however diligently one had served as a public citizen or privately as a paterfamilias in the rather patriarchal structure of ancient Greek family life, there was still the risk that life could end badly.
This means that happiness does not consist in whatever you might be feeling — after death, of course, you might not be feeling much at all — but in what others feel about you.