 Bacon, Francis |  Carneades |  Comte, Auguste |  Descartes, René |  Galen |  Hegel, Georg Wilhelm Friedrich |  Kant, Immanuel |  Leibniz, Gottfried Wilhelm |  Montaigne, Michel de |  Platonism: in the philosophy of mathematics |  Ramus, Petrus |  Sextus Empiricus |  skepticism: ancient |  Wittgenstein, Ludwig 