The subject of this essay-based dissertation is Hume’s natural philosophy. The dissertation consists of four separate essays and an introduction. These essays do not only treat Hume’s views on the topic of natural philosophy, but his views are placed into a broader context of history of philosophy and science, physics in particular. The introductory section outlines the historical context, shows how the individual essays are connected, expounds what kind of research methodology has been used, and encapsulates the research contributions of (...) the essays. The first essay treats Newton’s experimentalist methodology in gravity research and its relation to Hume’s causal philosophy. It is argued that Hume does not see the relation of cause and effect as being founded on a priori reasoning, similar to the way in which Newton criticized non-empirical hypotheses about the causal properties of gravity. Contrary to Hume’s rules of causation, the universal law does not include a reference either to contiguity or succession, but Hume accepts it in interpreting the force and the law of gravity instrumentally. The second article considers Newtonian and non-Newtonian elements in Hume more broadly. He is sympathetic to many prominently Newtonian themes in natural philosophy, such as experimentalism, critique of hypotheses, inductive proof, and the critique of Leibnizian principles of sufficient reason and intelligibility. However, Hume is not a Newtonian philosopher in many respects: his conceptions regarding space and time, the vacuum, the specifics of causation, the status of mechanism, and the reality of forces differ markedly from Newton’s related conceptions. The third article focuses on Hume’s Fork and the proper epistemic status of propositions of mixed mathematics. It is shown that the epistemic status of propositions of mixed mathematics, such as those concerning laws of nature, is that of matters of fact. The reason for this is that the propositions of mixed mathematics are dependent on the Uniformity Principle. The fourth article analyzes Einstein’s acknowledgement of Hume regarding special relativity. The views of the scientist and the philosopher are juxtaposed, and it is argued that there are two common points to be found in their writings, namely an empiricist theory of ideas and concepts and a relationist ontology regarding space and time. (shrink)

IThere are various ways of being a sceptic. Most obviously, perhaps, versions of scepticism can differ with respect to scope. Scepticism can be universal; it can be directed against beliefs belonging to certain broad kinds, say beliefs having to do with the external world; or it can be quite focussed, as in the case of religious scepticism. But there is also the question of force. Some philosophers treat scepticism as a purely theoretical affair, defining it as the thesis that knowledge (...) is impossible. This kind of scepticism, theoretical scepticism, has no essential connection with any particular sceptical practice. A theoretical sceptic does not necessarily entertain doubts or suspend judgment about any particular matter of fact or theory. He may think that the problem of induction is insoluble yet not be seriously concerned that the sun will not rise tomorrow. But in other versions, the force of scepticism is taken to be practical, in which case to be a sceptic is to entertain doubts or suspend judgment, and not just to take a certain theoretical position in epistemology. (shrink)