He who fears death fears either unconsciousness or another sort of consciousness. Now if you will no longer be conscious you will not be conscious either of anything bad. If you are to take on a different consciousness, you will be a different being and life will not cease.
Men are born for the sake of each other. So either teach or tolerate.
An arrow flies in one way, the mind in another. Yet even when it is keeping on the alert or circling round an inquiry, the mind moves no less directly, and straight to its target.
Enter into the directing mind of everyone, and let anyone else enter your own.
I love how Marcus approaches the perceived fear of death. Death is nothing else but oblivion or a new consciousness. If oblivion, then you won't feel or fear anything. If a different consciousness, then you get another chance to learn to practice Stoicism!
Another excellent summation of our duties towards others: either tolerate or teach. No need to complain if someone is bothering you. Either put up with it patiently or make the effort to teach them and help them be better.
This next passage is a but cryptic, but from what I can get out of it, it seems to be saying that mind is able to reason to the point (the conclusion).
And the last passage of Book 8 says nothing more than: share. Share your thoughts; give your reasons. And let others share their thoughts and reasons. Transparency helps everyone arrive at better decisions. Open and active debate is the foundation of a prosperous civilization.
(see also Citadel p. 225, 258)