Hume’s Radical Empiricism: Knowledge and Critique
David Hume and Radical Empiricism
The philosophy of David Hume represents the most radical empiricist approach, both regarding the theory of knowledge and its application to other philosophical areas such as ethics or criticism of religion. Hume was inspired by the work of Locke and Berkeley, but went far beyond them in his critique of metaphysics (so much so that Kant himself recognized his debt to him).
In our discussion, we will try to present Hume’s philosophy based on a single philosophical principle, the semantic principle, and then deduce the consequences of this principle. This principle is the materialization of empiricist positions we have seen since the start of the topic.
We will start with the first principle from which we will develop all of Hume’s empiricist philosophy. It is necessary to clarify the concept: what are impressions? For Hume, all our ideas are nothing but copies of our impressions of the immediate data of our experience (whether external or internal). Therefore, everything originates from sensory experience, referring to the world of the senses, as in Berkeley. However, we must differentiate between the initial perceptions, which are more intense and direct, and ideas, which are perceptions of a “second grade,” i.e., less active or intense. Hume starts from all our initial perceptions, sensations, and feelings to arrive at reflection. Therefore, as we said before, when in doubt about the meaning of a word (which happens sometimes with philosophical terms), we must find the sensitive impression from which the term derives. If we cannot find any impression on which to base that term, then we are using an empty term without meaning.
The Theory of Knowledge in Hume
From the semantic principle, Hume develops another principle that could be called syntactic, which is the classification of our ideas based on whether they come from direct or indirect experience. It reads:
The conclusion is clear: physics, not about relationships between ideas, but on questions of fact cannot imply propositions that are always true, as in mathematics. The clearest case in which we can see the radical nature of Hume’s position is the well-known example of billiard balls. With the “hypothesis of Adam,” Hume tells us that a human being who has not had prior experience cannot infer that when a billiard ball hits another, the second is due to move. Experience sets limits to our knowledge, and we cannot overcome them. Moreover, nothing in our experience allows us to infer that something is the cause and the other the effect: all we can grasp is that the first thing happens, then the other. Alternation, succession in time, does not imply any necessity. We do not perceive any sensation related to the concept of cause. Then, applying the semantic principle, Hume criticizes the misuse of the principle of causality in metaphysical practice: there is nothing in my experience that would suggest the idea of power or necessary connection.
Hume’s criticism of metaphysics extends not only to the use of empty slogans like substance but also to the external world through criticism of the principle of causality. Remember that thanks to this principle, Descartes or Locke themselves had not doubted the truth of the outside world. But Hume has something more to say:
We can never say with certainty the existence of the outside world, but that we do not care to live. The only thing that Hume wants to show with this criticism is the excessive confidence of the rationalists and empiricists in some human capabilities, and the belief in the continued independent existence of the outside world is so ingrained in our minds that it is impossible to uproot. But this does not mean we can prove it, as claimed earlier philosophers, not even our own existence. Thus, the concept of self or soul, then fundamental to the history of philosophy, also shows us as the last redoubt metaphysical. If we apply the same criticism I’ve done in the case of billiard balls, if we ourselves do not we have more to loose prints, frames, or memories of our own existence, then where dwells the course ‘I ” spoken of by the other philosophers? The “I” appears as a “bundle of perceptions”, as the river of Heraclitus in constant evolution.