On Friday June 21, 15-17h, Kenneth Westphal (University of East Anglia and Bielefeld University) will give a lecture at the Faculty of Philosophy of VU University Amsterdam. The event is a combined initiative of the Sections on Historical and Theoretical Philosophy. Title: Which is more constructive, realism or empiricism? How Kant and Hegel undergird Newton's causal realism and undermine Van Fraassen's constructive empiricism. Discussants: Christan Krijnen and Hans Radder. Location: Senaatszaal (room 2E-57), 2nd floor, E-wing, main building VU, De Boelelaan 1105, Amsterdam. For directions, see here: http://www.vu.nl/nl/over-de-vu/contact-routebeschrijving/routebeschrijvingen/index.asp. Abstract: Kant’s Critique of Pure Reason contains an original and powerful semantics of singular cognitive reference which has important implications for epistemology and for philosophy of science. Kant, however, did not realize the full implications of this cognitive semantics for these domains. In the Phenomenology of Spirit (1807) Hegel adopted and justified Kant’s semantics of singular cognitive reference, without appeal to Transcendental Idealism (nor to any similar view), and showed how it suffices to refute pre-Critical metaphysics, empiricism, rationalism and scepticism, whether Pyrrhonian, Cartesian or empiricist. Hegel further showed that this semantics of singular cognitive reference directly and strongly supports Newton’s methodological Rule 4 of experimental Philosophy in ways which support Newton’s realism about gravitational force. The textual and exegetical issues involved in these attributions to Hegel I address elsewhere. Here I make Hegel’s important finding available to philosophers and historians of science, by beginning with Newton’s Rule 4 of Philosophy and its role in Newton’s justification of realism about gravitational force (§2;  per Harper 2011). Next I briefly summarize Hegel’s semantics of singular cognitive reference (§3), and then show that it is embedded in and strongly supports Newton’s Rule 4, and that it rules out not only Cartesian physics (per Harper) but also Cartesian, infallibilist presumptions about empirical justification generally (§4). This result exposes a long-neglected fallacy in Bas van Fraassen’s key argument for his anti-realist Constructive Empiricism, and in many common objections to realism (§5). These problems reveal yet a further important regard in which Constructive Empiricism is not (so to speak) ‘empirically’ adequate, not even to Classical Newtonian Mechanics (§6). This inadequacy of Constructive Empiricism highlights a chronic empiricist misunderstanding of Newton’s mechanics (§7). Finally, Hegel’s cognitive semantics improves upon the semantic interpretation of scientific theories, and rectifies the presumption that laws of physics literally ‘lie’ (§8). Thus Hegel and Newton still have invaluable lessons for contemporary philosophy and history of science (§9).