Cicero says that philosophizing is nothing other than getting ready to die. That is because study and contemplation draw our souls somewhat outside ourselves, keeping them occupied away from the body, a state which both resembles death and which forms a kind of apprenticeship for it; or perhaps it is because all the wisdom and argument in the world eventually come down to one conclusion; which is to teach us not to be afraid of dying.

[ … ]

That is why all rules meet and concur in this one clause. It is true that they all lead us by common accord to despise pain, poverty and the other misfortunes to which human lives are subject, but they do not do so with the same care. That is partly because such misfortunes are not inevitable. (Most of Mankind spend their lives without tasting poverty; some without even experiencing pain or sickness). It is also because, if the worse comes to worse, we can sheer off the bung of our misfortunes whenever we like: death can end them. But, as for death itself, that is inevitable.

And so if death makes us afraid, that is a subject of continual torment which nothing can assuage. There is no place where death cannot find us – even if we constantly twist our heads about in all directions as in a suspect land: It is like the rock for ever hanging over the head of Tantalus. Our assizes often send prisoners to be executed at the scene of their crimes. On the way there, take them past fair mansions and ply them with good cheers as much as you like. Do you think they can enjoy it or that having the final purpose of their journey ever before their eyes will not spoil their taste for such entertainment?

He inquires about the way; he counts the days; the length of his life is the length of those roads. He is tortured by future anguish.

The end of our course is death. It is the objective necessarily within our sights. If death frightens us how can we go one step forward without anguish? For ordinary people the remedy is not to think about it; but what brutish insensitivity can produce so gross a blindness? They lead the donkey by the tail:

They walk forward with their heads turned backwards.

No wonder that they often get caught up in a trap. You can frighten such people simply by mentioning death; and since it is mentioned in wills, never expect them to draw one up before the doctor has pronounced the death-sentence. And then, in the midst of pain and terror, God only knows what shape their good judgement kneads it into!

[…]

Death can surprise us in so many ways:

No man knows what dangers he should avoid from one hour to another.

[…]

[After describing a number of examples of random death]

When there pass before our eyes examples such as these, so frequent and so ordinary, how can we ever rid ourselves of thoughts of death or stop imagining that death has us by the scruff of the neck at every moment?
You might say: ‘But what does it matter how you do it, so long as you avoid pain?’ I agree with that. If there were any way at all of sheltering from Death’s blows – even by crawling under the skin of a calf – I am not the man to recoil from it. It is enough for me to spend my time contentedly. I deal myself the best hand I can, and then accept it. It can be as inglorious or as unexemplary as you please.

But it is madness to think you can succeed that way. They come and they go and they trot and they dance: and never a word about death. All well and good. Yet when death comes – to them, their wives, their children, their friends – catching them unawares and unprepared, then what storms of passion overwhelm them, what cries, what fury, what despair! Have you seen anything brought so low, anything so changed, so confused?

We must start providing for it earlier. Even if such brutish indifference could find lodgings in the head of an intelligent man it sells its wares too dearly. If death were an enemy which could be avoided I would counsel borrowing the arms of cowardice. But it cannot be done. Death can catch you just as easily as a coward on the run or as an honourable man.

It hounds the man who runs away, and it does not spare the legs fearful backs of unwarlike youth;

no tempered steel can protect your shoulders;

No use a man hiding prudently behind iron or brass: Death will know how to make him stick out his cowering head;

we must learn to stand firm and to fight it.
To being depriving death of its greatest advantage over us, let us adopt a way clean contrary to that common one; let us deprive death of its strangeness; let us frequent it, let us get used to it; let us have nothing more often in mind than death. At every instant let us evoke it in our imagination under all its aspects. Whenever a horse stumbles, a tile falls or a pin pricks however slightly, let us at once chew over this thought: ‘Supposing that was death itself?’ With that, let us brace ourselves and make an effort. In the midst of joy and feasting let our refrain be one which recalls our human condition. Let us never be carried away by pleasure so strongly that we fail to recall occasionally how many are the ways in which that joy of ours is subject to death or how many are the fashions in which death threatens to snatch it away. That is what the Egyptians did: in the midst of all their banquets and good cheer they would bring in a mummified corpse to serve as a warning to the guests.

We do not know where death awaits us: so let us wait for it everywhere. To practice death is to practice freedom. A man who has learned how to die has unlearned how to be a slave. Knowing how to die gives us freedom from subjection and constraint. Life has no evil for him who has thoroughly understood that loss of life is not an evil.

[…]

In truth risks and dangers do little or nothing to bring us nearer to death. If we think of all the millions of threats which remain hanging over us, apart from the one which happens to appear most menacing just now, we shall realize that death is equally near when we are vigorous or feverish, at sea or at home, in battle or in repose.

If I have only one hour’s work to do before I die, I am never sure I have time enough to finish it. The other day someone was going through my notebooks and found a declaration about something I wanted done after my death. I told him straight that, though I was hale and healthy and but a league away from my house, I had hastened to jot it down because I had not been absolutely certain of getting back home. Being a man who broods over his thoughts and stores them up inside him, I am always just about as ready as I can be: when death does suddenly appear, it will bear no new warning for me. As far as we possibly can we must always have our boots on, ready to go; above all we should take care to have no outstanding business with anyone else.

Why, in so brief a span do we find strength to make so many projects?

We shall have enough to do then without adding to it.

On man complains less of death itself than of its cutting short the course of a fine victory; another, that he has to depart before marrying off his daughter or arranging the education of his children; on laments the company of his wife; another, of his sons; as though they were the principal attributes of his being.

I am now ready to leave, thank God, whenever He pleases, regretting nothing except life itself – if its loss should happen to weigh heavy on me. I am untying all the knots. I have already half-said my adieus to everyone but myself. No man has ever prepared to leave the world more simply nor more fully than I have. No one has more completely let go of everything than I try to do.

We ought not to plan anything on so large a scale – at least, not if we are to get all worked up if we cannot see it through to the end.

I want us to be doing things, prolonging life’s duties as much as we can; I want Death to find me planting my cabbages, neither worrying about it nor the unfinished gardening.

[…]

Wherever your life ends there all of it ends. The usefulness of living lies not in duration but in what you make of it. Some have lived long and lived little.
Michel de Montaigne (1603) Essays: To Philosophize is to learn how to die