There are a variety of notions as to what consciousness is. Some people denote consciousness simply as the difference between being awake/aware and asleep/unaware. Neuroscience posits consciousness as being various neural oscillations (Block 2002), but is still unclear as to how meaning is generated in the brain (Crick and Koch 1998). One of the most important features of consciousness, its subjectivity, is reported by Searle to be a neurobiological process (Searle 1980), or the notion of ‘what it is like to be’ by Thomas Nagel (Nagel 2002). According to Ned Block (2002), various notions of consciousness cause confusion and Block’s paper, Concepts of Consciousness, wishes to clarify and define consciousness through separating it into two distinct categories- phenomenal consciousness and access consciousness. This essay will argue that Block fails to establish such a separation which does not help his cause of clarification.
Block (2002, p.206) describes the concept of consciousness as a ‘mongrel concept’ which is used in describing a variety of concepts to identify different phenomena. Block (2002) disputes these different phenomena being treated as a single concept, and he wishes to divide consciousness into recognizable states in order to provide clarity and certainty for people when they discuss consciousness. By categorising consciousness into two main types: phenomenal consciousness (P-consciousness) and access consciousness (A-consciousness), Block (2002) contends that one type of consciousness is based upon non-physical phenomena and the other is based upon the physical functioning of the brain.
Block (2002) theorises that P-consciousness is based upon perceptual experience, not simply the state of awareness that one is in when one is awake. P-conscious properties can be referred to as ‘what it is like’ to have states such as pain, sight, hearing, smell, taste, and experiential properties of sensations such as thoughts, desires and emotions (2002, p. 206). Block (2002) also contends that such conscious states can make an intentional difference and can be representational. However, Block also holds that P-conscious states can be held distinct from any cognitive, intentional, or functional property, namely A-consciousness. A-consciousness is non-phenomenal consciousness and it is based upon its functionality. Block (2002) maintains that it is used for reasoning, reporting, and the direct control of rational action. One of the relationships between P and A consciousness is that A consciousness reports on the information gathered from P-consciousness.
Another relationship between the Block’s two concepts of consciousness is that although each type is distinct it also interacts with the other (2002, p.210). For example, when perceptual information is accessed it can change the intentional direction of thought, or as Block puts it, it ‘can change figure to ground and conversely, and a figure-ground switch can effect one’s phenomenal state’ (2002, p.209). In Block’s (2002) view an experience’s content can be in both conscious states at once because of the phenomenal properties of one and the representational properties of the other. However, there are three main differences between these two types of consciousness. Firstly, P-consciousness is phenomenalwhile A-consciousness is representational. Block (2002) remarks that the content of P-consciousness is the ‘what is like’ component and this allows the content of an experience to be both P-conscious and A-conscious. Secondly, A-consciousness is functional, or as Block (2002, p.209) declares: ‘…what makes a state A-conscious is what a representation of its content does in a system’. Thirdly, P-consciousness can be a type of ‘kind of’ state. For example, if pain is a P-conscious type then every pain must have that feel, whereas A-consciousness could sometimes fail to be accessible. Block sums up these differences by maintaining that P-conscious states are sensations, whereas A-conscious states involve ‘propositional attitudes’ such as thoughts, beliefs and desires, representational states expressed by ‘that’ clauses. (2002, p. 209).
As Block’s intention is to define these states of consciousness so that they can be properly identified and not confused, he needs to show that the relationship between both P and A consciousness can be separated. To do this Block (2002) gives particular examples of A-consciousness without P-consciousness, such as a computational robot that is identical to a person but that does not experience phenomenal or perceptual states. To act, the robot needs to receive information. Even the simplest computer needs information and it does not seem plausible that the robot would be able to do any computing at all if there was not data entered into it. That would appear to make it an inanimate object. Therefore, with data or information taking the place of perceptual states and phenomenal experience needing these states to provide information, this example of A-consciousness without P-consciousness does not seem credible.
Another example that Block (2002) gives of A-conscious states without P-consciousness, is the blindsight patient, who can guess that there is an ‘X’ rather than an ‘O’ in his blind field. For someone to have knowledge of this ‘X’ so that they could guess it was there, they must have some previously gathered experience or knowledge of that ‘X’. An analogy to this example could be my guess as I am driving that there is a motorcyclist in my car’s blindspot from my previous perception in my rearview mirror of her travelling in the same direction as me but in a different lane. I would only think about the motorcyclist, or the ‘X’ in the case of the blindsight patient, if I had previous knowledge or experience of it. Unless we are talking about assumed innate thoughts, I cannot have thoughts about something of which I have no previous knowledge or experience. Therefore, Block’s analogy seems not to succeed on this account.
Block (2002) keeps on with his blindsight analogy with a person who has superblindsight. He states that this superblindsighted person can guess that there is a horizontal field in his blind field purely though introspection, in the way that Block (2002 p.211) says we can solve problems simply through thoughts popping into our minds, or the way that one might just innately know the time, or which way North is without experiencing it. This superblindsight example is contentious because resolutions to problems need to be based upon some experience or knowledge. Even our knowledge of North, without having some perceptual experience such as it being pointed out, is debatable. The concept of North would not have any meaning. It seems that the only way A-consciousness could be a state without P-consciousness would be to conclude, as Descartes did, that ‘even bodies are not strictly perceived by the senses or the faculty of imagination but by the intellect alone, and that this perception derives not from being touched or seen but from their being understood’ (Descartes, 2002, p. 13). Such an assumption of innate knowledge makes this analogy appeal to belief, rather than prove a truth.
Block (2002) also claims that P-consciousness without A-consciousness is possible. To be P-conscious without being A-conscious, one would be perceptually aware without being able to transmit that information into useful data. An objection arose to this claim which states that we would never be in the position to know whether P-consciousness without A-consciousness is possible. Block (2002) responds to this objection in his paper by arguing that introspection would allow us to be aware of our consciousness and to see it as being distinct from A-consciousness. This is a contradictory response, as to be introspectively aware would be putting A-consciousness to use thereby one would be P-conscious as well as A-conscious. The truth of the claim of P-conscious states without A-conscious states also appears unconvincing.
Block’s intention to differentiate various concepts of consciousness in order to counteract confusion seems to end up being confused itself. Intuitively, there does not seem to be any problem thinking about consciousness as being perceptual on the one hand and functional on the other. These two types seem to work together to underpin a functioning mind. However, there is confusion between the two types, with A-consciousness being found by Block (2002) to be indeterminate and P-consciousness sometimes straying into the realm of A-consciousness through having properties such as thoughts, wants and emotions ( 2002, pp.207-08). Although we can assume Block does not see such states as thoughts and desires being functional, these could be categorised as functional activities of the brain.
Computational approaches to the mind see access consciousness being identical to phenomenal consciousness because of its function of information gathering and processing (2002, p.208). So is the categorical statement that Block puts forward true: If P = A then the computational model of the mind is correct? Phenomenality and accessibility consciousness are considered features of consciousness, as are intentionality, subjectivity, qualia, self-consciousness, unity and dynamic flow etc. (Gulick 2004). However, this does not mean that being identical features of a single concept or that being part of many features of consciousness allows the computational model to be correct. There were other models of the mind that were not necessarily computational before Block made his claims. Furthermore, computational models of the mind are not necessarily correct for other reasons, such as the binding problem (Crick and Koch 1998). From the number of features of consciousness, it appears that it has a multidimensional rather than a singular or dichotomic quality.
Block argues that his claim needs his two consciousness types to be able to be conceptually separated. For me, he fails to establish this. Without empirical or conceptual evidence, it is like stating that a single or multiple thing/s are necessarily two separate categories simply because they have been put into two separate ‘files’. Therefore, I do not think that Block’s model of consciousness as a single theoretical perspective is plausible.
Block, N 2002 ‘Concepts of Consciousness’, in D Chalmers (ed), Philosophy of Mind: Classical and Contemporary Readings, Oxford University Press, New York
Crick, F, Koch, C 1998, ‘Consciousness and Neuroscience’, Cerebral Cortex, no.8, pp. 97-107, viewed 3rd May 2012 http://www.klab.caltech.edu/~koch/crick-koch-cc-97.html
Descartes, R 2002, ‘Meditations on First Philosophy’ in D Chalmers (ed) Philosophy of Mind: Classical and Contemporary Readings, Oxford University Press, New York
Nagel, T 2002, ‘What it is like to be a bat’ in D Chalmers (ed) Philosophy of Mind: Classical and Contemporary Readings, Oxford University Press, New York
Searle, JR 1980, ‘Minds, Brains, and Programs,’ Behavioral and Brain Sciences, no. 3, pp.417-457, viewed 3rd May 2012 http://users.ecs.soton.ac.uk/harnad/Papers/Py104/searle.prob.html
Van Gulick, R 2004, “Consciousness”, in Edward N. Zalta (ed.), The Stanford Encyclopedia of Philosophy (Summer 2011 Edition), viewed 5th May 2012 http://plato.stanford.edu/archives/sum2011/entries/consciousness/