Protagoras versus Socrates
Diogenes versus Plato
Aristotle versus Plato
Eudoxus versus Aristotle
Epicurus versus Zeno
Sextus Empiricus versus Marcus Aurelius
Augustine versus Hypatia
Anselm versus Abelard
Thomas Aquinas versus Roger Bacon
William of Ockham versus Duns Scotus
Thomas Hobbes versus Ren e Descartes
Blaise Pascal versus Pierre de Fermat
John Locke versus Thomas Hobbes
Gottfried Leibniz versus Baruch de Spinoza
David Hume versus Jean-Jacques Rousseau
Immanuel Kant versus Adam Smith
Edmund Burke versus Thomas Paine
Jeremy Bentham versus John Stuart Mill
Friedrich Engels versus Karl Marx
Charles Darwin versus Gregor Mendel
Karl Marx versus Charles Darwin
Georg Cantor versus Bertrand Russell
Bertrand Russell versus John Dewey
Ludwig Wittgenstein versus David Hilbert
Oskar Morgenstern versus John von Neumann
Karl Popper versus Ludwig Wittgenstein
Jean-Paul Sartre versus Simone de Beauvoir
John Nash versus John von Neumann
Rudolph Carnap versus Leonard Savage
Imre Lakatos versus Karl Popper
Robert Nozick versus David Lewis
John Rawls versus John Harsanyi
Derek Parfit versus John Rawls.