Hume Meets Descartes

In this essay, I will demonstrate that the Cogito is not simply classable into the two seemingly distinct categories of human inquiry known as Relations of Ideas and Matters of Fact. The Cogito is diverse and draws from both concepts in defining itself. The Cogito itself is far too vague and needs a description before it can be classified. The categories under which the Cogito will be classified need a similar sort of investigation before they are taken to be absolute.

The distinction between relations of ideas and matters of fact must first be made clear before any further work is undertaken. Bear in mind that the distinction is between all the objects of human inquiry. The distinction can be made clear best by using David Hume’s own words. “Every affirmation, which is either intuitively or demonstratively certain.” seems to be a Relation of Ideas, whereas Matters of Fact encompass all other forms of human inquiry that are not Relations of Ideas (Hume inquiry 15). This distinction is in no way arbitrary, but rather arises out of necessity: as Hume himself said, these are ‘natural’ distinctions. All matters of fact are based on a strong Cause and Effect relation. For example, we eat a pie in hopes that it will nourish us. The idea that pie nourishes us is a matter of fact. Without causes or effects, no matters of fact would be present. Matters of fact are reasons that tie together all the perceptions of the human experience. Hume later goes on to suggest that no causal structures are grounded in reason due to the ‘secret’ powers of nature. This devastating suggestion makes matters of fact extremely weak in terms of rational certainty. To be more precise, all Matters of Fact are contradictable and not deductively provable. Relations of Ideas on the other hand are ideas that exist outside space and time. They are clear to all human creatures and are deductively provable. Hume considers the sciences of “Geometry, Algebra and Arithmetic” to be prime examples of relations of ideas. The key idea to note here is that Hume claims that relations of ideas can exist for humans regardless of anything at all in the universe.

At this point in time the distinction may seem extremely clear and of a simple a priori and a posteriori nature. Let us therefore consider the distinction as an epistemic one for now and further look at it. Before we do this however, we must consider Hume’s vision of the world. Impressions are what the human experience imposes on the human while ideas are what the human creates from impressions. Ideas are limited “to no more than the faculty of compounding, transposing, augmenting, or diminishing the materials afforded us by the senses and experience” (Hume inquiry 11). The reality of ideas can never exceed impressions, thus impressions must give rise to all human ideas. Without an impression, there can be no idea rooted in it. Now when we consider the epistemic distinction it seems clear that Relations of Ideas are all reasonings that are a priori, whereas Matters of Fact are weak a posteriori reasonings. This is quite contrary to what Hume had said in Section Two of the Enquiry. Since all ideas are based on impressions, it is impossible for there to be any a priori reasonings at all! It is unbelievable to see how quickly Hume builds a compounding thesis and then ignores it to accommodate the seemingly a priori reasonings present in the human experience.