A Reflexive Science of Consciousness

ABSTRACT

Classical ways of viewing the relation of consciousness to the brain and physical world make it difficult to see how consciousness can be a subject of scientific study. In contrast to physical events, it seems to be private, subjective, and viewable only from a subject's first-person perspective. But much of psychology does investigate human experience, which suggests that classical ways of viewing these relations must be wrong. An alternative, Reflexive model is outlined along with it's consequences for methodology. Within this model the external phenomenal world is viewed as part-of consciousness, rather than apart-from it. Observed events are only "public" in the sense of "private experience shared." Scientific observations are only "objective" in the sense of "intersubjective." Observed phenomena are only "repeatable" in the sense that they are sufficiently similar to be taken for "tokens" of the same event "type." This closes the gap between physical and psychological phenomena. Indeed, events out-there in the world can often be regarded as either physical or psychological depending on the network of relationships under consideration.

However, studying the experience of other human beings raises further complications. A subject (S) and an experimenter (E) may have symmetrical access to events out-there in the world, but their access to events within the subject's body or brain is asymmetrical (E's third-person perspective vs S's first-person perspective). Insofar as E and S each have partial access to such events their perspectives are complementary. Access to S's experience is also asymmetrical, but in this case S has exclusive access whereas E can only infer its existence. This has not prevented the systematic investigation of experience, including quantification within psychophysics, psychometrics, and so on. Systematic investigation merely requires that experiences be potentially shared, intersubjective and repeatable. In this the conditions for a science of consciousness are no different to a science of physics.

I am always rather puzzled when people ask whether it is possible to have a science of consciousness, for the reason that much of psychology is a science of consciousness in spite of it's frequent protestations to the contrary. Many of the papers to follow, for example, will elaborate on recent ways in which psychological and related brain sciences are getting on with the study of conscious experience rather than agonizing over whether such a study is possible, and this has been true of experimental psychology since it's inception in Wundt's Leipzig laboratory. How, for example, could one study colour vision, perceptual illusions, emotions, dreams, imagery, and the like, without making a systematic study of conscious experience, it's relation to environmental input, to brain processing, and so on?

So, why is it that in much philosophical, psychological, and other scientific writing a scientific investigation of consciousness has been thought to be difficult if not impossible? The reason, I suggest, has to do with a deep-seated confusion about how consciousness relates to the brain and physical world, that permeates the entire Dualist vs Reductionist debate.

Figure 1. A Dualist model of the causal sequence in visual perception. Light rays from a cat (as-perceived by an Experimenter) impinge on the Subject's eye. Impulses travelling up the optic nerve produce a neural representation of the cat within S's central nervous system. CNS activity, in turn, has a causal influence on S's mind, resulting in a percept of a cat. It is central to this model that the percept (of a cat) in the mind of S is quite separate both from the neural representation (of a cat) in S's brain and the cat (as-perceived by E) out-there in the world (taken from Velmans, 1990).

Consider, for example, the conventional model of perception shown in Figure 1. Viewed from the perspective of an external observer E, light rays travelling from the physical object (the cat as-perceived by E) stimulate the subject's eye, activating his optic nerve, occipital lobes, and associated regions of his brain. Neural conditions sufficient for consciousness are formed, and result in a conscious experience (of a cat) in the mind of S. From E's perspective, the physical and neurophysiological causes of S's experience are (in principle) observable, but not their perceptual effect (the experience itself). E nevertheless infers that S has an experience, for the reason that when he turns his gaze toward the cat he experiences it himself.

It is clear from this simple model why consciousness is often thought to elude scientific study. From E's perspective, the cat is seen to be out-there in the world; it appears to be public, objective, and viewable from an external, third-person perspective. Consequently, a scientific study of cats presents no philosophical problems. By contrast, S's experiences seem to be private, subjective, and viewable only from S's first-person perspective. If so, how can they form a data-base for science? Dualists and Reductionists have very different reactions to this problem. For Dualists, S's experience may be a non-material substance or entity, with no location or extension in space (represented as a "cloud" in Figure 1); consequently, Dualists may accept that a study of consciousness is beyond natural science. For Reductionists, S's experience will eventually be shown to be nothing more than a state or function of the brain (Figure 2). If so, the study of consciousness may be safely left to some future neurophysiology.

Figure 2. A Reductionist model of the causal sequence in visual perception. Light rays from a cat (as-perceived by an Experimenter) impinge on the subjects eye. Impulses travelling up the optic nerve produce a neural representation of the cat within S's central nervous system. This CNS activity is subjectively experienced as a percept of a cat (in the mind of S) but neurophysiological discoveries will show this subjective experience to be nothing more than a state of or function of S's brain (taken from Velmans, 1990).

I do not intend to rehearse