30 Phil, Chapter 16, Al-Farabi, Touchstone 41: Existence.

Metaphysics, the branch of philosophy exploring being and reality, investigates what exists and how they exist. You are born a human, you can’t change that, but the essence of you, your identity either evolves as you age or you were born with your identity. In 350 BCE, Plato proposed a realm of Forms and said you are born with it all. Aristotle disagreed. In about 1000 CE, Avicenna said your “essence precedes your existence.” In the 1900s, Sartre comes along and says nope again, “your existence precedes your essence.” Meanwhile, science has largely sided with Aristotle and Sartre.