Question: Baal HaSulam writes that there are 10% of altruists in the world. If the Creator created the ego, have these altruists been created in order to set an example?
Answer: In spirituality, 10% of altruists (in relation to the tenth part of the Partzuf) sustain the world. In our world, we need the same thing. If the world were made of 100% egoists, it could not exist.
There must be altruistic egoism, even with the intention for my own sake, in order to dilute this world a bit.
From the Kabbalah Lesson in Russian 2/26/17