I remember years ago when I was much younger being rhetorically cornered by the Ayn Rand fanatics who demanded to know if I thought human beings are fundamentally good or evil. When I refused to answer that question, they would always accuse me of being evasive. I'm not being evasive. The question is ridiculous.
Jean Jacques Rousseau said that we are all basically good, that it is civilization corrupting us by alienating us from virtuous Nature and our original natural selves.
John Calvin said that we are all fundamentally evil, that we are all wicked depraved rebels against God and His laws.
If we are all so wonderful, then why all the crime and violence? "Nature averse to crime?" said the Marquis de Sade in reply to Rousseau, "I tell you Nature yearns in all her pores for bloodshed."
If we are all so wicked, then why did Adam and Eve not fall irrevocably into the Lake of Fire with Lucifer and his rebellious angels? asked WH Auden in a poem.
Human beings, like all other animals, are selfish. Our animal priorities are to gratify our desires and to avoid pain. That is neither particularly good or particularly evil. That's just the way things are. Complexity begins when all of us struggle to move beyond that basic nature, either for good or for evil.
As far as I'm concerned, Rousseau and Calvin are wrong for the same reason. Their views of human nature are both abstract and reductive.