Consistently With Reason

If our intellectual part is common, the reason also, in respect of which we are rational beings, is common; if this is so, common also is the reason which commands us what to do; if this is so, there is a common law also; if this is so, we are fellow citizens; if this is so, we are members of some political community; if this is so, the world in a manner is a state. For of what other common political community will anyone say that the whole human race are members? And from thence, from this common political community comes also our very intellectual faculty and reasoning faculty and our capacity for law; or whence do they come? For as my earthly part is a portion given to me from certain earth, and that which is watery from another element, and that which is hot and fiery from some particular source (for nothing comes out of that which is nothing; as nothing returns to non-existence), so also the intellectual part has a common source.

One man, when he has done a service to another, is ready to set it down to his account as a favor conferred. Another is not ready to do this, but still in his own mind he thinks of the man as his debtor, and is aware of what he has done. A third in a manner does not even know what he has done, but he is like a vine which has produced grapes, and seeks for nothing more after it has once produced its proper fruit. As a horse when he has run, a dog when he has caught game, a bee when it has made honey, so a man when he has done a good act, does not call out for others to come and see, but he goes on to another act, as a vine goes on to produce again the grapes in season. Must a man then be one of these, who in a manner acts thus without observation.

-Personal Memoirs of Emperor Marcus Aurelius (121-180 AD)