There are many proponents depending upon the age/stages of the development of Philosophy.
Pre-Socractic = Thales of Miletus, Colopon, Anaximander
Greek Golden Age = Socrates, Plato, Aristotle
Medieval Ages = St. Thomas Aquinas, William of Oakham
Modern Philosophy = Rene Descartes, John Paul Sartre
Contemporary = Sparshot, Howard Slusher.
There are only the few proponents of Philosophy