- Immanuel Kant
- Jean-Jacques Rousseau
- René Descartes
- John Locke
- John Stuart Mill
- Thomas Hobbes
- John Miller Dow Meiklejohn
- Baruch Spinoza
- Georg Wilhelm Friedrich Hegel
- Edmund Burke
- Arthur Schopenhauer
- Ludwig Wittgenstein
- Gottfried Wilhelm Leibniz
- George Berkeley
- Erasmus
- Thorstein Veblen
- A.J. Ayer
- Nicolaus Copernicus
- Frederick Gustav Weiss
- Seymour Feldman