Avira, Rambam, in his introduction to “Shemoneh Perakim” says that he took from non-Jewish philosophers. In the Guide, he quotes Aristotle and various Molem philosophers and then contrasts them with his view. This is also a common explanation of יפת אלקם ליפת וישכון באהלי שם.
In any case, I was discussing altruism, which is a general concept.
I found that gemara you cited. It’s Baba Batra 10b. The maskana is Rabban Yochanan ben Zakkai’s interpretation, which is what the Malbim says.