A Version of Direct Realism

Here, I explain the sense in which sensory perception provides direct awareness of the external world.*

[ *Based on: Skepticism & the Veil of Perception, ch. 4. ]

Background: In the theory of perception, there are traditionally four views:

1. Direct realism: In perception, we are directly aware of the external world. Also, we have non-inferential knowledge about the external world.

2. Indirect realism (sometimes called “representationalism”, but this could be misleading): In perception, we are directly aware only of something in our own minds, and we are indirectly aware of the external world. Also, we have (only) inferential knowledge about the external world.

3. Idealism: In perception, we are directly aware of our own minds (or “ideas” in the mind), and there is no external world.

4. Skepticism: Nobody knows whether there is an external world.

Most philosophers who endorsed any of these have endorsed (2), though the issue is not often discussed today. Most psychologists would also endorse (2), though perhaps without knowing what it means. Let’s start by understanding what (1) and (2) mean.

1. Awareness

Here, I am interested in “awareness” as a relationship between a conscious being and an object of which the being is aware. There are different kinds of awareness: E.g., perception (perceptual awareness) is direct awareness of external objects, events, or other phenomena. Knowledge is awareness of facts. Memory is awareness of past events or previously-learned facts. Concepts are states of awareness of abstract objects (universals). At least some intuitions constitute awareness of necessary truths.

Since my thesis is phrased in terms of awareness, I should say something about what awareness is. For S to be aware of x, three things must happen:

(i) S must have an assertive mental representation.

Comment: This is a type of mental state that represents its content as actual (such as perceptual experiences or beliefs, and unlike mere imaginings or desires).

(ii) x must (exist and) at least roughly satisfy the content of that representation, at least in some important respects. And

(iii) It must be non-accidental (not merely a matter of chance) that the content of the representation is satisfied.

2. Direct vs. Indirect Awareness

The distinction between direct and indirect awareness is a generalization of the distinction between non-inferential and inferential knowledge.

You are “indirectly aware” of x when your awareness of x is based on your awareness of something else. You are directly aware of x when your awareness of x is not based on awareness of anything else.

What is this “basing” relation? It is both causal and logical. A mental state M2 is based on mental state M1, roughly, when M1 causes M2 (by a non-deviant causal chain) partly in virtue of the (apparent) logical relationship between the content of M1 and the content of M2. Inference is an example: when you infer Q from P, your belief that P causes your belief that Q in virtue of the apparent logical connection between P and Q. Another example is that perceptual beliefs are based on perceptual experiences.

So the question between direct and indirect realism comes down to whether our awareness of external phenomena is based on awareness of mental phenomena.

3. Perception

3.1. The existence of perceptual experience

Perception is a form of awareness in which the assertive mental representation is a perceptual experience. This is a purely internal mental state, which is common to normal perceptions, illusions, and hallucinations.

Oddly enough, some philosophers deny the existence of perceptual experiences. They claim that there is no mental state in common between normal perceptions and hallucinations; there are just two completely different states, “perception” (which entails the existence of an external object that one is aware of) and “hallucination” (in which there is no such object).

What’s the argument that perceptual experiences exist? Probably the best argument is the Hallucination Argument:

1. It is possible to have a hallucination caused by a brain state qualitatively identical to the brain state that would occur during normal perception. (As in, e.g., the brain-in-a-vat scenario.)

2. In such a case, that brain state causes a purely internal mental state.

3. In general, if you duplicate the penultimate stage of a causal sequence (i.e., the stage right before the ultimate effect), then you duplicate the effect.

4. Therefore, during normal perception, there also occurs a purely internal mental state.

3.2. Content-satisfaction

To count as perceiving an object, you need to have a perceptual experience that at least roughly accurately represents some important features of the object (typically, its shape and color, in the case of visual perception). There can be some amount of distortion (as in the case of illusions), compatible with your still perceiving an object. However, if an external object causes you to have an experience that just fails to correspond at all to the nature of that object, then you’re not perceiving the object; you’re just hallucinating.

E.g., when you take LSD and, let’s say, have an experience as of a pink squirrel, that experience does not count as perceiving the LSD, because the LSD molecules are not pink and squirrel-shaped.

3.3. Causation

Finally, the third thing that must happen when you perceive something is that the thing that (roughly) satisfies the content of your perceptual experience must cause that experience (in the normal way). More precisely, there must be a systematic, causal connection between features of the object and features of the experience.

4. The Nature of Perceptual Experience

4.1. Qualia

Let’s talk more about what perceptual experiences are like. First, most of them have qualia, i.e., there is a particular qualitative character to the experience, “something it is like” to have that experience.

Some philosophers deny the existence of qualia, or deny that the qualia of our experiences are something over and above their representational content. E.g., some think that the difference between what it’s like to see red and what it’s like to see green is solely a matter of the experiences’ representing different properties.

Perhaps the best argument that qualia are something more than just representational content is the inverted color spectrum argument:

You can imagine someone with an inverted spectrum of color experiences, with green and red qualia swapped. E.g., when they look at grass, they have an experience qualitatively like the experience you have when you look at ripe tomatoes, and vice versa.

In such a case, it would be arbitrary to claim that your experiences are “more correct” than theirs, or that they must be suffering illusions while you are perceiving normally. (If this helps, imagine that half the population has one set of experiences, while the other half has the inverted experiences.)

So both people are perceiving colors equally correctly.

If so, they must both have the same representational content (otherwise, one of them would have content that doesn’t match reality).

But they don’t have the same experience. So qualia are something over and above representational content.

4.2. Representational content

Why think that experiences have representational content?

One reason is that the notion of their representational content is needed to explain the difference between perceiving things normally (correctly) and having an illusion or hallucination. It is also needed to explain how perceptual experiences lead us to form beliefs. And how we can form concepts referring to certain kinds of things based on our experiences. If our experiences did not contain any content—if they did not represent the world to be a certain way—then all of these things would be a mystery.

By the way, please do not confuse either representational content or propositional content with conceptual content. (The latter confusion is mind-bogglingly common among professional philosophers.)

Perceptual experiences have propositional content, in the sense that they represent the world to be a certain way. (Propositions are ways the world might be.)

To have conceptual content is another matter: it is a matter of having content in a way that depends on one’s grasp of certain concepts. Perceptual experiences can have both conceptual and non-conceptual content. E.g., your visual experiences represent certain very specific shades of color which you do not have concepts for, so that’s non-conceptual content. At the same time, you can, e.g., see something as a duck or as a rabbit, where this depends on your already having the concept of a duck or the concept of a rabbit, so that is conceptual content.

4.3. Forcefulness

Lastly, perceptual experiences have an attribute I call their “forcefulness”—the characteristic that, when you have one of these experiences, it seems as though you are actually, presently confronted with the object of the experience. This is unlike, say, imagination, in which it does not seem that the thing you are imagining is actually present.

5. Is This Direct Realism?

Now you can see why Direct Realism is true:

During perception, you have a perceptual experience (per §3.1). This counts as an assertive mental representation, due to its representational content (§4.2) and its forcefulness (§4.3).

When you are perceiving (rather than hallucinating), the perceptual experience’s content is roughly satisfied by an external object (§3.2), and this is non-accidental due to the causal connection between the object and the experience (§3.3).

So you satisfy all the conditions given in §1 for counting as “being aware of” the external object.

Is this awareness direct or indirect? It is direct, since it it not based on awareness of anything else. Your perceptual experience is caused by the external object (and your brain states, etc.), but it is not caused by any other state of awareness, so it does not count as “indirect awareness”.

In particular, notice that your awareness of external objects is not based on awareness of internal, mental states. When you have a perceptual experience, the object of awareness (the thing of which you are aware) is the thing that satisfies the content of the experience, which is an external thing, not a mental state. You could of course also be aware of your mental states, by introspection. But this would not be the cause of your perceptual experience, so your perceptual experience would not be based on that introspective awareness.

6. The Mistake of Indirect Realism

The central error of indirect realists has always been to confuse a vehicle of awareness with an object of awareness. Or (as Mortimer Adler puts it), to confuse that by which we are aware of things with that of which we are aware.

We are aware of external objects, and the way in which we are aware of them is by having perceptual experiences. Those experiences are what make us count as being aware of the external things; they are not themselves the things we are normally aware of. More precisely, they are not the things we are aware of by virtue of perceiving. (Again, you can be aware of a perceptual experience, by introspectively reflecting on your experience. But that would be another state of awareness. Perception itself does not consist of being aware of perceptual experiences.)

This error, by the way, was famously committed by Locke (who declared that “ideas” are the objects of human knowledge). Berkeley then picked it up and used it to argue for idealism. Once you grant that the things we are aware of are always “ideas”, it’s hard to resist Berkeleyan arguments that maybe the ideas are all that there is.

Fortunately, we can avoid that error. Most of the things we are aware of are just the real, physical things around us.