The Virtues of Direct Realism

I’m at the APA meeting in Denver now. I’m speaking at a group meeting tomorrow morning (the Society for Realist/Antirealist Discussion). So here I will give a summary of my talk (which is also a summary of my chapter in the book Direct versus Indirect Realism, ed. John Smythies and Robert French), so no one will have to get up before 8:30 in the morning to go:

1. Epistemological DR versus IR

There are multiple ways of defining “direct” and “indirect realism”. But here I want to focus on epistemological issues. So here is a formulation of an epistemological version of the dispute:

Direct Realism (DR) holds that normal perception gives us non-inferential justification for certain external-world propositions.

Indirect Realism (IR) holds that normal perception gives us inferential justification, and only inferential justification, for external-world propositions.

I assume that skepticism and idealism are false, so this is just about the debate between IRists and DRists. Note that no one claims that every perceptual experience justifies what it appears to reveal (you could, e.g., have reason to think you’re hallucinating). Also note that IR is a universal generalization, but DR is not: DRists only claim that some external-world prop’s are justified non-inferentially. IRists claim that none are.

2. A Version of DR

How could DR be true? Well, there is a good theory of justification called “Phenomenal Conservatism” (PC). It holds that P has at least some justification, provided (i) that it seems to you that P, and (ii) you have no reason to doubt this appearance. Note that on this theory, the appearance is enough to confer justification (absent grounds for doubt); it is not required that you first prove that appearances are reliable indicators of the facts they purport to represent, etc. No other beliefs are required in order to have justification; nevertheless, other beliefs can defeat the justification, if you should have beliefs that imply that the appearance is untrustworthy.

In perception, what appears to us to be the case is some external-world proposition. What appears to be the case is not some mental proposition. E.g., it appears that there’s a table in front of me; it doesn’t appear that there’s a table-like mental image. So, on PC, we get non-inferential justification for the external-world propositions, as long as we lack grounds for doubt.

I’ve argued for PC in other work, and I’m not going to repeat all that now. (See my book, Skepticism and the Veil of Perception, and the papers “Compassionate Phenomenal Conservatism” and “Phenomenal Conservatism and the Internalist Intuition”.) Here, I’m just going to explain 2 problems for IR that DR avoids.

3. The Basing Problem

This is the first problem. According to IRists, our justification for external-world beliefs depends upon arguments like the following:

A.   I am having a table-like sense-datum (or mental image, etc.).

B.    The best explanation for A is that there is a real, physical table (existing independent of my mind).

• This requires ruling out things like the brain-in-a-vat scenario, etc.

C.    Therefore, probably there is a real table.

All of our external world beliefs are supposed to have something like that justification. (Note: you can substitute other inferences if you like. The inference-to-the-best explanation is the most common approach, though.)

Now here is the basing problem.

1.    The Basing Requirement for justified belief: A belief is (doxastically) justified only if it is based on something that is an adequate source of justification for the proposition believed.

2.    We do not in fact base our external-world beliefs on anything like the inference A-C above.

3.    So, if IR is true, our external world beliefs are unjustified.

This would be a very undesirable result for the IRist. Notice that DR has no such problem. On DR (as defended by me), appearances are an adequate source of justification for what appears to be the case. Since we actually base our external-world beliefs on the appearances, there is no problem with our beliefs being justified.

4. The Asymmetry Problem

Here is the 2nd problem for IR. The IRist says that a perceptual appearance isn’t enough for justification, that we always have to rely on other justified propositions, which would ultimately have to be provided by other cognitive faculties (introspection, intuition, memory, reasoning). These other faculties could not themselves be treated in the same way; otherwise, there would be an infinite regress. So the IR’ist must hold that for (at least some) non-perceptual appearances, the appearance is enough for justification, without the need of other justified propositions.

E.g., the IRist thinks that to be justified in believing there’s a table in front of me, I have to use introspection and reason to justify something like claims A and B above. More generally, I have to have an argument that my sensory appearances are a good indicator of facts in the external world. But I don’t (on their view) have to construct any parallel arguments to justify relying on introspection or reasoning – I don’t have to prove that introspective or intellectual appearances are good indicators of the facts that they seemingly inform me of. Again, if I did have to do that, I’d be epistemically screwed, since there’s going to be an infinite regress.

So the IRist posits an epistemological asymmetry between perception and our other cognitive faculties. But, I claim, there is no good rationale for such an asymmetry. Now, here of course, one has to look at candidate rationales. I claim (and argue in the book chapter) that none of the following suggestions work: (i) that perception is uniquely prone to error, (ii) that perception is prone to different kinds of error than other faculties, (iii) that other faculties give us “acquaintance” but perception doesn’t.

An IRist could of course rebut me here by offering a different rationale for the asymmetry and defending it. But, until there is such a rationale, DR is superior to IR. DR doesn’t postulate an unmotivated asymmetry: it treats all appearances & all cognitive faculties alike, as having a presumption of veridicality until we are given grounds for doubt.

5. Summary

Those aren’t all the arguments for DR, nor have I addressed all the forms of DR that are interesting. But those are two important theoretical advantages for epistemological DR over epistemological IR:

i.     The Epistemological Direct Realist can recognize our actual perceptual beliefs as properly based, while the Epistemological Indirect Realist must say that our actual perceptual beliefs are unjustified, irrational, not knowledge-constituting, etc.

ii.    The Epistemological Indirect Realist, unlike the Direct Realist, must posit an unmotivated epistemological asymmetry, treating some but not all cognitive faculties as basic sources of justified belief.