What is the unique and most important feature that distinguishes man from all other living beings?

Why is it that, contrary to the instinct of self-preservation, a parent will throw themselves headlong into fire or water to save their child?

Why do people get married and why do they get divorced? Why do people have extra-marital affairs and why do two people in a couple become jealous of one another? What is Love?

When and why did the type of sex emerge among human beings that is free of any reproductive function?

Why are the social and...