Nature's law. Seneca, Epistles 4.30.11-12

Seneca continues his meditation on death, the great equalizer.

Mors necessitatem habet aequam et invictam: quis queri potest in ea condicione se esse in qua nemo non est? prima autem pars est aequitatis aequalitas. Sed nunc supervacuum est naturae causam agere, quae non aliam voluit legem nostram esse quam suam: quidquid composuit resolvit, et quidquid resolvit componit iterum. Iam vero si cui contigit ut illum senectus leviter emitteret, non repente avulsum vitae sed minutatim subductum, o ne illum agere gratias diis omnibus decet quod satiatus ad requiem homini necessariam, lasso gratam perductus est. Vides quosdam optantes mortem, et quidem magis quam rogari solet vita. Nescio utros existimem maiorem nobis animum dare, qui deposcunt mortem an qui hilares eam quietique opperiuntur, quoniam illud ex rabie interdum ac repentina indignatione fit, haec ex iudicio certo tranquillitas est. Venit aliquis ad mortem iratus: mortem venientem nemo hilaris excepit nisi qui se ad illam diu composuerat.

Death holds us all in the same invincible grip: for who can complain of being in a condition that nobody escapes? Occupying the same state is the chief part of being alike, being equal. But it is pointless here to spend our effort making nature's case, since she is unwilling to allow us any law beyond her own: whatever she has done, that she will undo, and once she has undone a thing, she puts it back together again. Happy the man who stumbles late upon a gentle death, sinking slowly under the weight of old age rather than have his life torn away suddenly. He should render thanks to all the gods that he has reached the final rest of humankind so full and fulfilled, sated and weary with life's experience so that death offers sweet reprieve. Your own eyes witness how certain people generally prefer to choose death rather than beg for life. I don't know which folks give us more courage, in my own opinion: those who demand death, challenging her to do her worst, or those who await her calmly and joyfully. The challenge rises from rage and reckless disdain, while peaceful resignation comes from a firm resolution. Anyone might come to death angry or enraged, but nobody ever received her happily unless he had long prepared himself to do so.