Is Perception Always Experiential? (by guest blogger Joshua Rust)
In an earlier post, Eric asked the question, "Is There an Experience of Thinking?". In this post I would like to look at a related question—is perception always experiential?
Given the amount of philosophical ink spilled on this question, I think it will be more helpful to proceed indirectly by reframing it as an interpretive question.
First, some background: if the question concerns the role phenomenal properties play in perception, there are two broad classes of answer. On one hand, phenomenalists argue that phenomenal properties are necessary for perception (Chalmers, Pitt, Siewert, G. Strawson). On the other hand, representationalists argue that a phenomenal experience is not necessary for sensory experience (Dennett, Brandom, McDowell, Rey, Sellars), or else is reducible to perception's intentional content (Dretske, Lycan, Tye). For more background see Pitt's excellent entry on mental representation in the Stanford Encyclopedia of Philosophy (especially sections 3-5).
Now, the interpretive puzzle: Pitt includes John Searle within the phenomenal camp. He claims that Searle thinks that phenomenal properties are necessary in determining the content of sensory experience. While there is much in Searle which supports Pitt's characterization of Searle, I have recently come across a passage in Intentionality which suggests Searle's considered view is otherwise: while phenomenal conscious properties are "characteristic" of perception, for Searle, they are not necessary.
Searle is clear that beliefs need not have phenomenal experience. But perceptions are different: (A) "States such as beliefs and desires need not be conscious states. A person can have a belief or desire even when he is not thinking about it and he can be truly said to have such states even when asleep. But visual and other sorts of perceptual experiences are conscious mental events" (Intentionality, 45).
He then goes on to assert that, (B) "Someone who claimed that there was a class of beings capable of perceiving optically, that is, beings capable of visual perception but who did not have visual experiences, would be making a genuine empirical claim" (Intentionality, 46).
Given what he says in (B), one would expect that Searle would then cite empirical evidence which would buttress his claim in (A), that in order to percieve one must have some sort of conscious, phenomenal experience. He does go onto cite empirical evidence, but it doesn't appear to justify the claim made in (A).
(C) "Weiskrantz, Warrington and their colleagues have studied how certain sorts of brain lesions produce what they call 'blind sight'. The patient can give correct answers to questions about visual events and objects that he is presented with, but he claims to have no visual awareness of these objects and events. Now, from our point of view the interest of such cases derives from the fact that the optical stimuli the patient is subjected to apparently produce a form of Intentionality. Otherwise, the patient would not be able to report the visual events in question. But the Intentional content produced by their optical stimulation is not realized in the way that our presentational contents are realized. For us to see an object, we have to have visual experiences of a certain sort. But, assuming Weiskrantz's account is correct, the patient can in some sense 'see' an object even though he does not have the relevant visual experiences. He simply reports a "feeling" that something is there, or makes a "guess" that it is there. Those who doubt the existence of visual experiences, by the way, might want to ask themselves what it is that we have that such patients seem to lack" (Intentionality, 47)
To my ear, Searle appears to misconstrue the significance of the 'blind sight' evidence. If blind sight tests show that we can see without having certain phenomenal experiences (C), given that Searle holds that phenomenal experiences must be present in order to see is an empirical claim (B), then the blind sight test seems to contradict his claim in (A) that perceptual experience is a conscious mental event.
Questions: are there are alternative readings of these passages which saves Searle from incoherence? Given (C), is Pitt wrong to characterize Searle as a phenomenalist about visual experience in the SEP article? More generally, is a phenomenal experience necessary for perception? If so, is there any way for the phenomenalist to make sense of the Weiskrantz "blind sight" findings?