David Hume Enquiry Concerning Human Understanding Questions
David Hume was a Scottish empiricist.
Empiricism is an umbrella term for philosophical theories of epistemology (the study of knowledge) that argue that knowledge of the world is acquired a posteriori: through sense experience (seeing, touching, hearing, measuring, etc.). This is to be contrasted with Rationalism(which argues that ultimate knowledge is acquired a priori: through the use of reason and the understanding alone, independently of sense data).
Hume argues that claims about the nature of reality that are NOT based on some possible sensory experience are ultimately meaningless (because they cannot be confirmed or refuted).
To give a somewhat trivial example, consider the following:
During medieval times, scholastics used to have heated debates about the number of angels that can dance on the head of a pin.
For Hume, since angels (assuming they even exist!) cannot be seen or detected (since seeing requires the presence of some kind of physical material that either produces or reflects light particles), then all such talk is ultimately meaningless and a waste of our time (for, even if a particular answer happens to be true, it’s not one that we could actually know to be true).
One of the fascinating things about Hume’s epistemology is that he used his theory to reach a lot of very strange conclusions about the nature of the justification for many of our beliefs, showing in the process that we don’t have an epistemic right to many of them. The most obvious would be God or supernatural entities or forces in general, but what makes Hume so interesting is that he went much further, and this theory of knowledge applies everywhere:
- We have no rational justification for our expectation that events should conform to “the laws of nature,” since such “laws” cannot actually be experienced (all we can experience are particular events and objects, but not universal rules). This insight, by the way, helped inspire Einstein to attempt to overthrow Newtonian mechanics. In fact, in a letter to a friend, Einstein explicitly acknowledged Hume’s influence on him. And this is why we refer to Einstein’s insights as his “Theories of Relativity,” and not (as we had previously done with Newton), as his “Laws of Relativity.”
- We have no actual experience of causality (the idea that one object has a causal influence on another), only the experience that certain events tend to be followed by certain other events (but the ‘connection’ between these is not one that we actually ever experience).
- We have no rational, non-circular basis on which to base scientific claims (Hume was an advocate of science, to be sure, but he saw that at its heart there is a vacuum: you can’t use science to justify science).
- Our knowledge of the world is literally superficial: it is knowledge of surfaces (what things look like, sound like, taste like, etc.). We don’t have any access to any kind of internal “essence” of things. So, what do you know about your beloved? Well, literally only the surface: what they look like, what they sound like, what they feel like to the touch, what they smell like, and what they taste like. What’s hiding behind those beautiful eyes? Who knows? But maybe the eyes are the windows to the soul? Well, we’ve already seen how Lucretius mocks that cliché.
- Most perplexingly, Hume argued that any talk of our “self” or “essence” is meaningless rubbish: we have no actual experience of a “self” or of some internal “essence.” All we can experience is perceptions, bodies and behavior, but not something “internal” which has those experiences.
Notice that this has huge implications for our study of Love:
Hume argues, first of all, that “I” don’t have any sensory experience that “I” actually exist as some kind of unified self. “I” am simply a bunch of perceptions floating around.
And if “I” don’t seem to exist, then how can “I” love “myself”?
But, of course, if “I” don’t exist, then neither do “you.” And if “you” don’t exist, then how can “I” love “you“?
What do I know about you? My perception of you is always of your sensible qualities (what I can see, hear, touch, etc.). I have no access to your “essence” (whatever that may be: your mind, your thoughts, your feelings, etc.). Sure, I can hear the sounds that “you” make when you speak, and I assume that those match the reality of “you” (assuming there is such a thing to begin with), but I can’t actually know that. Perhaps this helps to explain so many instances in which we thought we knew someone, only to find later on that we were sadly mistaken?
This is a direct challenge to someone like Plato, who argued that “Real Love” is the love of the “essence” (and not of the contingencies) of another. Hume might ask: What essence? Isn’t “essence” just another version of angels dancing on the head of a pin? And we should take such talk seriously? Really?
As you can probably see, Hume’s challenges have proved incredibly difficult to overcome (and we’ll get to the question of the self later).
In order to understand Hume more properly, it’s important to get a sense for the broader intellectual context, both scientific and philosophical, under which he is operating.
The two main empiricist of the early modern period on whose work Hume builds are John Locke and Bishop George Berkeley (pronounced Barkley: he was Irish), and although Hume does not make explicit mention of it, a significant portion of his work is a response to Locke’s distinction between primary and secondary qualities, ultimately siding more with Berkeley on this question:
If you are interested in a more serious introduction to the empiricism of Locke and Berkeley (which would be helpful to contextualize Hume’s own ideas), the following discussion between Bryan Magee and Michael Ayers is a great place to get started:
In addition to the distinction between primary and secondary qualities, it is also important to get a sense for the broader intellectual context, both scientific and philosophical, under which Hume is operating.
Aristotle’s teleological approach to our understanding of causality—which was pretty much orthodoxy for about two thousand years—argues that events take place because the universe has built-in purposes and strivings in which objects have a potential that they seek to actualize: it’s why acorns, unconscious though they may be, strive to become oak trees, why rocks fall down, fire rises up, and why substances that have a dormitive property make you sleepy. Christianity liked this teleological metaphysics, and added the notion of God as the creator of those purposes. With God at the helm, the idea of purposes now seemed to make the universe rational and intelligible.
For the early modern philosophers, this kind of teleology may (or may not) work for biological organisms (it’ll take Darwin to fully undermine this notion more than a century later), but given the work of scientists such as Copernicus, Kepler, Galileo and others, natural philosophers such as Descartes, Hobbes, Galileo, Boyle & Newton developed a different understanding of physics based on the notion of material particles interacting with each other through mechanical causation.
Roughly speaking, in a game of billiards, if the cue ball moves in the direction of the 8-ball and touches it, the motion from the former will transfer over to the latter, and will move it depending on the angle of impact. For these modern thinkers, this means that not only can we come up with an after-the-fact explanation for how objects seem to behave the way they do (like Aristotle’s teleological metaphysics, though without the circularity that plagued his kind of account), but we can do one better: we can calculate and make very accurate quantitative predictions, all by appealing to geometry, as with Descartes, plus the concept of forces. Though this is a radical departure from Aristotle (after all, this is a pretty direct rejection of teleological purposes), these modern thinkers thought (as we’ve already seen with Descartes), that we can still preserve the intelligibility of the universe: it is still a universe governed by rational laws that can be understood through mathematics, logic and reason.