Commentary on Meditations: B9:29

The universal cause is a torrent, sweeping everything in its stream. So, man, what does that mean for you? Do what nature requires at this moment. Start straight away, if that is in your power: don't look over your shoulder to see if people will know. Don't hope for Plato's Utopian republic, but be content with the smallest step forward, and regard even that result as no mean achievement. How worthless are these little men in the public eye who think their actions have anything to do with philosophy! They are full of snot. And who will change their views? Without a change of view what alternative is there to slavery - men groaning and going through the motions of compliance? Go on, then, talk to me now of Alexander and Philip and Demetrius of Phalerum. I shall follow them, if they saw the will of universal nature and took themselves to her school. But if they simply strutted a dramatic role, no one has condemned me to imitate them. The work of philosophy is simple and modest. Do not seduce me to pompous pride.

Life is extremely complex, or at least it can seem that way.  Despite all that complexity and the vastness of time and space, you still only must decide what you are going to do right now.  That is all over which you have control.  And how do you boil everything down - how do you get it from the complex to the comprehensible - so that you can decide how to use your time and actions now?  Simply put, reason.  Furthermore, the Stoics applied their reasoning and arrived at the conclusion of “virtue is the sole good.”  Therefore, if you funnel all your choices and thinking into the paradigm of "virtue is the sole good" then you will see this complex world through the lens of wisdom, justice, courage and temperance.

Extending that concept to society and civilization; Plato perhaps saw society as full of philosophers where everyone was enlightened.  It is a worthy goal.  But philosophically herding humans is far more difficult than herding cats.  Therefore, any progress you make in enlightening others ought to be celebrated as no small (mean or average) achievement.

Further in the passage, Marcus seems to be saying the alternative to enlightenment (philosophy) is slavery, which he defines as "groaning" and "going through the motions" - certainly no joy in that!  Then he seems to defend men who at least preached that everyone ought to live a life philosophically, but perhaps were hypocrites ("simply strutted a dramatic role").  To which Marcus responds he certainly has the capacity to listen to reason from hypocrites, but he is not condemned to act as the hypocrite - he can take the lesson without having to act like the (bad) teacher.  A modern-day rendition of this idea is "don't throw the baby out with the bathwater."  To be clearer, however, I think the ideal scenario is to learn philosophy from sages - true Stoic sages who live what they teach.

(see also Citadel p. 271, 303-305)