Everything changes

Anything you see is passing as time passes; not one of the things we see stays put. I myself, even as I tell you of these changes, have changed. - Seneca, Moral Letters, 58

Earth becomes water, water becomes air, and the air becomes fire. There is the same kind of transformation the other way around.  - Musonius Rufus - Stobaeus 4.44.60

Even nature changes

Nature controls everything. But nature itself keeps changing

Nature, which controls everything, will soon change all that you see and use it as material for something else. It will do so over and over again, so the world is always new. - Marcus Aurelius, Meditations 7.25

Everything is impermanent 

In this constantly changing world, our time is limited. As we age, our bodies change. Soon we won’t be around anymore.

Your time is just a moment. You are constantly changing. Your senses are dimming. Your body is decaying. Your soul is spinning around. Your fortune is unpredictable. And your fame is doubtful. In short, your body is like a river. Your soul is like a dream and mist. Life is warfare, a brief journey to an alien land. After fame, obscurity. - Marcus Aurelius, Meditations 2.17

Before long, you will be no one, nowhere. Nothing you see now nor any of the people alive now will exist. All things are born to change, alter, and perish to make room for new things to come. - Marcus Aurelius, Meditations 12.21

Change is nothing to be afraid of

But there is nothing to worry about, assures Musonius Rufus. 

If you try to adapt your mind to these changes and accept voluntarily what cannot be avoided anyway, you will live a smooth and harmonious life. - Musonius Rufus Stobaeus 4.44.6)

Marcus Aurelius agrees:

Afraid of change? What can exist without change?  - Marcus Aurelius, Meditations  7.18

Nature’s task is to shift things everywhere, to move things from here to there, and transform them into this to that. Everywhere there is change, yet we need to fear nothing. All things – including the way they are arranged – are familiar to us. - Marcus Aurelius, Meditations 8.16

So how should we navigate in the ever-changing world? Here are some suggestions from Marcus Aurelius.

1. Become a student of change

From then on, you dedicate yourself wholly to the service of justice in whatever you do and nature in everything else. What people think or say or do against you is no longer your concern. Only two questions concern you now: 1. Is what you are doing the right thing to do? 2. Do you gladly accept whatever is given to you? All your cares and distractions are gone. You only want to walk the straight path of (the divine) law. - Marcus Aurelius, Meditations 10.11

2.  Keep in mind that everything is always changing

The universe is maintained by change – both in the basic elements and the things created by them. Be content to know these. Hold them as the basic principles. ... So, when the time comes to depart, you won’t complain but meet it with good grace, and genuine gratitude. So why fear it?  - Marcus Aurelius, Meditations 2.3

Acquire the ability to see how one thing changes into another. Constantly observe it. Use it to train yourself. Nothing will elevate your mind more because you realize that, at any moment, you may have to leave everything behind you, including the company of your friends and relatives.  - Marcus Aurelius, Meditations 10.11

3. Don’t get attached to ever-fleeting things 

Some things come into being quickly while others go out of it just as quickly. Even as a thing comes into being, some part of it is already gone. Change and fluidity constantly remake the world, just as the relentless flow of time remakes eternity.

In this running river, where can you find a firm foothold? What can you find of value among the many things that are rapidly passing you by? It is like attachment to a sparrow that is flying by you. In a moment the bird is gone. 

Your life is just an inhalation from the air and an exhalation from the blood. There is no difference between breathing a single breath (as we do every moment) and having the ability to breathe for a long time (as we have done since our birth) only to give it back someday to the source.  - Marcus Aurelius, Meditations 6.15

4. Let go of anxieties

You can get rid of many of the anxieties that disturb you now. They are just your opinion. Let your mind become spacious by allowing your thoughts to embrace the universe, contemplating the eternity, thinking about the speed with which things change, considering the short span between life and death, the boundless time before birth, and the boundless time after death. (9.32)

---