In William James’s “Will to Believe”, he defends the belief in faith (religion) without evidence on the grounds that all moral beliefs entail a degree of trust prior to sensible evidence. A situation may arise where one is unable to not make a choice (non-action is also a choice) before evidence abounds. The very consequence of holding a belief may influence the outcome as in the case of “confidence”. That is, evidence may not be realized unless a prior faith is constituted. Extending this to the religious sphere, one’s may never encounter proof of God unless one has placed in  God prior faith. Curiously enough, the scientific method is not so different in the sense that it makes hypotheses (albeit more verifiable) that begs/challenges forth an answer (evidence). This is typical of the “radical empiricism” of the modern age when neither observer nor observation can be frozen in time and separated; both facts and theories condition one another.

His ontology presupposes experience from which mater and thought enter into relations with. Pure experience is  “the immediate flux of life which furnishes the material to our later reflection with its conceptual categories”. That is, experience isn’t reduced to the objects of experience (Hume, Locke) which is wholly scientific but rather is imbued with both meaning and intentionality structured by human thought. Such a view also treats trans-empirical entities as superfluous as naturalistic accounts of meaning/intentions are sufficient explanations in practical terms.

John Dewey applies pragmatism to scientific inquiry where theories are judged accordingly to how well they predict phenomena in their respected domains; theories are instruments of prediction (instrumentalism) rather than laws that uncover truths about nature and thus relegated to approximations of truth. However, such a notion of truth is not absolute and appears at times appear probabilistic via statistical certainties. Instead, true/false can be viewed as a mutual adjustment between an organism (more on this side) and its environment; a satisfactory adjustment promotes a belief that has significance in the way that it induces behavior. The logic of belief follows inquiry which seeks to transform an undetermined situation into  a determined set of relations or a unified whole (Hegel’s influence). In the sphere of facts, this creates complications where the external consequences in a future are used to constitute facts; for example, one believes that they woke up this morning by virtue of not sleeping at the current moment rather than by looking at regularities of sleep cycles in the past. Such is the empowering yet dangerous element in Dewey’s philosophy where man, who has become unchained from the past, is able to make greater leaps forward in his own invention whilst being blinded by his own hubris.

Berkeley begins the modern idealist tradition with his complete rejection of material as metaphysical substance. Working from Locke, Berkeley’s immaterialism does not deny the existence of objects per-se, but that existence has become contingent on perceptions (of ideas or state-of-mind) by a subject. The subject, referred to as spirit, is analogous to the mind and “active” in the sense of possessing will/judgment and the aperception of ideas.  This is to say that there are no mind-independent things which leads to a fully subjective and restricted world-view; the existence of other spirits can only be known through the ideas that they incite in our minds. His moral philosophy is also contrarian to that of Locke; passive-obedience is a negative moral duty to the government without exceptions.

Hume both extended and finalized many of the issues that were contained in Locke and Hume’s empiricism. He’s most known for formulating the problem of induction or the inference of the unknown from known events. Underlying all of the induction is the assumption of uniformity or the regularity in nature; the observations that one makes thus far persists in both time and space outside that window. Such an assumption cannot be demonstrated as one can easily conceive of a world that is non-uniform. Neither can a probable argument towards its validity be meaningful as this is the very question that induction seeks to answer; logic/reason cannot be used to justify this hypothesis.

Hume’s notion of causality relates his conception of induction to man’s psychology. Here, causality is always preceded by the impressions of two conjoined events serialized in time. With repeated apprehensions, ideas or mental states of these impressions are formed such that the latter idea becomes associated with the former impression. The mind, by its necessity to determine relations, cannot help by make the leap to causation from its conditioning (Pavlov later demonstrates this in the 19th century). Related is his conception of the self as a mere bundle of perceptions; we have difficulty experiencing impressions of our self but instead have chains of perceptions that follow by necessity.

Hume’s ethics make an important distinction between reason/passion, is-ought, and moral responsibility in a compatibility view of free-will. Reason is always a slave (to serve) to passion in the sense that knowledge does not compel the will as does feelings/sentiments do. This follows from the formulation of the “is-ought” problem where no amount of descriptive statements can ever deduce a prescriptive statement. His compatablist’s free-will holds that while necessity binds actions to motives, it is the will that must have choice for otherwise the actions would be judged as only given to chance which non-regular.