Meditations 7:13

What is rational in different beings is related, like the individual limbs of a single being, and meant to function as a unit.

This will be clearer to you if you remind yourself: I am a single limb (melos) of a larger body—a rational one.

Or you could say "a part" (meros)—only a letter's difference. But then you're not really embracing other people. Helping them isn't yet its own reward. You're still seeing it only as The Right Thing To Do. You don't yet realize who you're really helping.