Allan Kardec. The book of spirits (№ 397584)

Question: Which of the vices can be seen as a radical?
Answer: We have said many times that this selfishness: it will expire all evil. Study all the vices and you will see that selfishness is present in the depths of each of them; you will in vain fight it, and you will not be able to eradicate them, as long as you do not encroach on the evil at the root, as long as you don't erase the cause. Let all your efforts tend towards this goal, for truly the plague of society here. Whosoever in this life to approach moral perfection, must root out from my heart every selfish feeling, for selfishness is incompatible with justice, love and mercy: it neutralizes all other virtues.