Direct and Indirect Realism - Problems With The Indirect Theory

Problems With The Indirect Theory

A problem with representationalism is that if simple data flow and information processing is assumed then something in the brain must be interpreting incoming data as a 'percept'. This something is often described as a homunculus, although the term homunculus is also used to imply an entity that creates a continual regress, and this need not be implied. This suggests that some phenomenon other than simple data flow and information processing is involved in perception. This is more of an issue now than it was for rationalist philosophers prior to Newton, such as Descartes, for whom physical processes were poorly defined. Descartes held that there is a "homunculus" in the form of the soul, belonging to a form of natural substance known as res cogitans that obeyed different laws from those obeyed by solid matter (res extensa). Although Descartes duality of natural substances may have echoes in modern physics (Bose and Fermi statistics) no agreed account of 'interpretation' has been formulated. Thus representationalism remains an incomplete description of perception. Aristotle realized this and simply proposed that ideas themselves (representations) must be aware - in other words that there is no further transfer of sense impressions beyond ideas.

A potential difficulty with representational realism is that, if we only have knowledge of representations of the world, how can we know that they resemble in any significant way the objects to which they are supposed to correspond? Any creature with a representation in its brain would need to interact with the objects that are represented to identify them with the representation. This difficulty would seem reasonably to be covered by the learning by exploration of the world that goes on throughout life. However, there may still be a concern that if the external world is only to be inferred, its 'true likeness' might be quite different from our idea of it. The representational realist would answer to this that 'true likeness' is an intuitive concept that falls in the face of logic, since a likeness must always depend on the way in which something is considered.

A semantic difficulty may arise when considering reference in representationalism. If I say "I see the Eiffel Tower" at a time when I am indeed looking at the Eiffel Tower, to what does the term "Eiffel Tower" refer? The direct realist might say that in the representational account we do not really see the tower but rather 'see' the representation. However, this is a distortion of the meaning of the word see which the representationalist does not imply. For the representationalist the statement refers to the Eiffel Tower, which implicitly is experienced in the form of a representation. The representationalist does not imply that when I refer to the Eiffel Tower, I am referring to my sense experience, and when you refer to the Tower, you are referring to your sense experience.

Furthermore, representative realism claims that we perceive our perceptual intermediaries-we can attend to them-just as we observe our image in a mirror. However, as we can scientifically verify, this is clearly not true of the physiological components of the perceptual process. This also brings up the problem of dualism and its relation to representative realism, concerning the incongruous marriage of the metaphysical and the physical.

The new objection to the Homunculus Argument claims that it relies on naive view of sensation. Because the eyes respond to light rays is no reason for supposing that the visual field requires eyes to see it. Not only are there no light rays in the head, but visual sensation (the argument can be extrapolated to the other senses) bears no direct resemblance to the light rays at the retina, nor to the character of what they are reflected from or pass through or what was glowing at the origin of them. The reason given is that they only bear the similarities of co-variation with what arrives at the retinas. Just as the currents in a wire going to a loudspeaker vary proportionately with the sounds that emanate from it but have no other likeness, so too does sensation vary proportionately (and not necessarily directly) with what causes it but bears no other resemblance to the input. This implies that the colour we experience is actually a cortical occurrence, and that light rays and external surfaces are not themselves coloured. The proportional variations with which cortical colour changes are there in the external world, but not colour as we experience it. Contrary to what Gilbert Ryle believed, those who argue for sensations being brain processes do not have to hold that there is a 'picture' in the brain since this is impossible according to this theory since actual pictures in the external world are not coloured. It is plain that Ryle unthinkingly carried over what the eyes do to the nature of sensation; A. J. Ayer at the time described Ryle's position as 'very weak'. So there is no 'screen' in front of cortical 'eyes', no mental objects before one. As Thomas Hobbes put it: 'How do we take notice of sense? -- by sense itself'. Moreland Perkins has characterized it thus: that sensing is not like kicking a ball, but rather 'kicking a kick'. Today there are still philosophers arguing for colour being a property of external surfaces, light sources, etc.

A more fundamental criticism is implied in theories of this type. The differences at the sensory and perceptual levels between agents require that some means of ensuring at least a partial correlation can be achieved that allows the updatings involved in communication to take place. The process in an informative statement begins with the parties hypothetically assuming that they are referring to the 'same' entity or 'property', even though their selections from their sensory fields cannot match; we can call this mutually imagined projection the 'logical subject' of the statement. The speaker then produces the logical predicate which effects the proposed updating of the 'referent'. If the statement goes through, the hearer will now have a different percept and concept of the 'referent' -- perhaps even seeing it now as two things and not one. The radical conclusion is that we are premature in conceiving as the external as already sorted into singular 'objects' in the first place, since we only need to behave as if they are already logically singular. The diagram at the beginning of this entry would thus be thought of as a false picture of the actual case, since to draw 'an' object as already selected from the real is only to treat the practically needful, but strictly false, hypothesis of objects-as-logically-singular as ontologically given. The proponents of this view thus argue that there is no need actually to believe in the singularity of an object since we can manage perfectly well by mutually imagining that 'it' is singular. A proponent of this theory can thus ask the direct realist feels why he or she thinks it is necessary to move to taking the imagining of singularity for real when there is no practical difference in the outcome in action. Therefore, although there are selections from our sensory fields which for the time being we treat as if they were objects, they are only provisional, open to corrections at any time, and, hence, far from being direct representations of pre-existing singularities, they retain an experimental character. Virtual constructs or no, they remain, however, selections that are causally linked to the real and can surprise us at any time—which removes any danger of solipsism in this theory. This approach dovetails with the philosophy known as social constructivism.

The character of experience of a physical object can be altered in major ways by changes in the conditions of perception or of the relevant sense-organs and the resulting neurophysiological processes, without change in the external physical object that initiates this process and that may seem to be depicted by the experience. Conversely any process that yields the same sensory/neural results will yield the same perceptual experience, no matter what the physical object that initiated the process may have been like. Furthermore the causal process that intervenes between the external object and the perceptual experience takes time, so that the character of the experience reflects, at the most, an earlier stage of that object than the one existing at the moment:s in observations of astronomical objects the external object may have ceased to exist long before the experience occurs. These facts are claimed to point to the conclusion that the direct object of experience is an entity produced at the end of this causal process, distinct from any physical object that initiates the process."