How does Marcus Aurelius use memento mori to curb desire for fame?

Marcus does not treat death as a separate topic from vanity. In Meditations 8.1 he starts from a plain fact about himself: it is too late for him to have lived his whole life, or even his life since youth, like a philosopher. Others can see this, and so can he. His reputation as a serious man is already compromised, and no effort now can undo the record.

That admission is the hinge. Most people chase reputation because they imagine there is still time to build the image they want, or to fix the one they have. Marcus removes that hope. If you have already fallen short of the picture you wanted others to hold of you, worrying about how you shall seem to others is a wasted motion (Meditations 8.1). The only thing left to do is live the rest of your life the way your own nature asks, not the way an audience would grade it.

This is where the memento mori comes in, though Marcus does not say the word death here. The whole force of the passage depends on a life that has a definite, closing shape: a youth already spent, a plan of life already set, a rest of your life that is genuinely the remainder, not an open field. Elsewhere in the Meditations he states the same structure more directly: since it is possible that you may depart from life this very moment, regulate every act and thought accordingly (Meditations 2.11). Fame is a project that only makes sense if you assume long stretches of future time to manage how you are perceived. Take the deadline seriously and the project collapses. There is no time left to spend on managing an image.

The common misreading treats this as a mood: think about dying and you will stop caring about petty things, the way fear of a doctor's diagnosis makes gossip feel small. Marcus is making a sharper claim than that. He has already tried the alternatives and found them empty: not in syllogisms, nor in wealth, nor in reputation, nor in enjoyment has he found happiness anywhere (Meditations 8.1). Reputation is not just distracting, it is one more externals that cannot deliver what it promises, and the shortness and unpredictability of life is what exposes this. He goes on, in a related passage, to argue that honour and dishonour happen equally to good people and bad, which is exactly why they cannot be goods at all (Meditations 2.11). Death makes this visible by removing the illusion that you can wait to secure a verdict from other people before you die.

What changes for someone who takes this seriously is not that they stop acting well in front of others, but that they stop needing the credit for it. The question shifts from how will this look to did this fit the kind of person I am trying to be. Marcus's own move, at the end of 8.1, is to redirect attention inward: observe what your own nature wills, and let nothing else distract you.

A concrete way to use this: before an action you are tempted to shape for an audience, a report, a decision, even a private habit, ask yourself whether you would still do it exactly this way if no one would ever hear about it. If the answer changes, you have found the part of the action that was serving fame, not the part serving your own excellence. Cut it.