Impermanence is usually associated with Buddhism. But it’s important in Stoicism too.
From Meditations by Marcus Aurelius
Existence is like a river
Everything’s destiny is to change, to be transformed, to perish – so that new things can be born (12.21).
Time is a river, a violent current of events, glimpsed once and already carried past us, and another follows and is gone (4.43).
Existence flows past us like a river: the “what” is in constant flux, the “why” has a thousand variations. Nothing is stable, not even what’s right here. The infinity of past and future gapes before us — a chasm whose depths we cannot see. It would take an idiot to feel self-importance or distress. Or any indignation, either — as if the things that irritate us lasted (5.23).
Life is like smoke
See human life for what it is. Smoke. Nothing. Especially when you recall that once things change they cease to exist for all eternity. Then why such turmoil? To live your brief life rightly, isn’t that enough? (10.31)
Before long everything will be transformed, to rise like smoke or be dispersed in fragments (6.4). All substance is soon absorbed into nature, all that animates it soon restored to the logos, all trace of them soon covered over by time (7.10).
All that you see will soon have vanished, and those who see it vanish will vanish themselves, and the ones who reach old age have no advantage over the untimely dead (9.33).
Everything that exists is already fraying at the edges and in transition, subject to fragmentation and decay. Everything was born to die (10.18).
Nature is like a sculptor
Nature takes substance and makes a horse, like a sculptor with wax. And then melts it down and uses the material for a tree. Then for a person. Then for something else. Each existing only briefly. It does the container no harm to be put together, and none to be taken apart (7.23).
Grapes. Unripe. Ripened. Then raisins. Constant transitions (11.35). Everything in flux. And you too will alter in the whirl and perish, and the world as well (9.19).
Have constant awareness that everything is born from change. The knowledge that there is nothing nature loves more than to alter what exists and make new things like it. All that exists is the seed of what will emerge from it. You think the only seeds are the ones that make plants or children? Go deeper (4.36).
Acquire the ability to see how all things change into one another. Apply it constantly. Use it to train yourself. Nothing is as conducive to spiritual growth (10.11).
This too shall pass
The speed with which all things vanish — the objects in the world, and the memory of them in time. Especially those that entice us with pleasure or frighten us with pain or are loudly trumpeted by pride. (2.12)
To understand those things — how stupid, contemptible, grimy, decaying, and dead they are — that’s what our intellectual powers are for. And to understand what those people really amount to, whose opinions and voices constitute fame. And what dying is — that if you look at it in the abstract and break down your imaginary ideas of it by logical analysis, you realize that it’s nothing but a process of nature, which only children can be afraid of (2.12).
Don’t fear change
Frightened of change? What can exist without it? What’s closer to nature’s heart? Can you eat food without transforming it? (7.18) There is nothing bad in undergoing change — or good in emerging from it (4.42). What follows is always in affinity with what went before. Not a random collection of things, but harmonious and interconnected (4.45).
Think of the whole of existence, of which you’re the tiniest part, how brief and fleeting your appointed time is, and how small a role you play in universal fate (5.24). By contemplating this you can discard most of the junk that clutters your mind — things that exist only there — and clear out space for yourself (9.32, see also 12.32).
What goes around comes around
Constantly bear in mind that all of this has happened before and will happen again — the same plot from beginning to end, the identical staging (10.27).
The world’s cycles never change — up and down, from age to age. Either the world’s intelligence wills each thing (if so, accept its will), or it exercised that will once and for all and all else follows as a consequence (and if so, why worry?). The waves of change and alteration, endlessly breaking – see our brief mortality for what it is (9.28).
So give yourself a gift: the present moment. People out for posthumous fame forget that the generations to come will be the same annoying people they know now. And just as mortal. What does it matter to you what they say or think? (8.44)
Human life in perspective
Condition of Body: decaying.
Soul: spinning around.
Lasting Fame: uncertain.
Summary: The body and its parts are a river, the soul a dream and mist, life is warfare and a journey far from home, lasting reputation is oblivion (2.17).
I am made up of substance and what animates it, and neither one can vanish into nothing, any more than it emerged from nothing. Every portion of me will be reassigned as another portion of the world, and that in turn transformed into another. Ad infinitum (5.13).
Reason & Virtue
I’ve shortened and arranged the quotations for readability. Quotations are from Gregory Hays translation published by Modern Library, a translation by Francis Hutcheson and James Moor and published by the Liberty Fund, Inc, and the Penguin Classics translated by Martin Hammond.