Commentary on Morsella, Godwin, Jantz, Krieger and Gazzaley, Behavioral and Brain Sciences
Note – this is an unedited preliminary draft of my commentary. Not for quoting.
An implicitly dualist or Cartesian materialist theory of consciousness is proposed without citing the many well-known problems with such theories. A function for consciousness is proposed with no reference to the possibility that ‘consciousness itself’ has no function of its own. The theory builds on proposed ‘subset consensus’ and ‘integration consensus’ when in the literature there is no such consensus on these issues.
From the first sentence this paper assumes that consciousness has a function. The authors never consider the possibility that it may not, and make many further assumptions that have frequently been challenged in the literature.
The question of function relates closely to what is probably the greatest gulf between theorists – whether consciousness is or is not something extra, or additional to, neural and biological processes. If it is, the hard problem (how subjective experiences arise from objective brain events (Chalmers 1995)) is real and consciousness must have evolved for a reason. If it is not, as in the case of the many variants of reductive or eliminative materialism, identity theory and physicalism, there is no hard problem and consciousness evolved because perception, memory, learning and other useful abilities evolved. Responding to the many well-known thought experiments, only those who think consciousness is something extra believe that philosophical zombies are possible and that Mary the colour scientist learns something new when she emerges from her black and white room (Jackson 1982).
The authors lie clearly in the first camp, not only with their concept of the ‘conscious field’ and its contents, but in their use of such phrases as “consciousness itself” (p 45), the “region responsible for consciousness” (p 30) and brain regions or processes “associated with consciousness” (p 9). They reject Cartesian dualism (explicitly claiming to avoid the homunculus fallacy) but admit to retaining aspects of the Cartesian theatre. So their theory is a version of Cartesian materialism (Dennett 1991), as revealed in such phrases as “contents enter consciousness” (p 38) and percepts and representations “become conscious” (pp 36, 43).
These phrases imply that some processes, percepts or representations are conscious while others are not, and the authors claim, as though it were uncontroversial, that there is a Subset Consensus on this issue. Citing Bleuler’s 1924 textbook they say “When adopting a descriptive standpoint, even the most cursory examination of the brain reveals a contrast between conscious and unconscious processes”. No, it does not. Examination with the naked eye reveals white and grey matter; with a microscope glial cells, neurons, axons and synapses; with modern scanning techniques further detail. Nowhere can we see what I have called the ‘magic difference’ (Blackmore 2011). They claim that “the contrast between conscious and unconscious processes in the brain is somewhat inevitable”. No. Not only is it not “inevitable”, it is deeply problematic. What could it mean? That some brain processes have subjective experiences attached to them; that some give rise to consciousness; that the hard problem applies to only a subset? Indeed, saying that a brain process is ‘conscious’ entails the mereological fallacy; ascribing to part of an animal “an attribute which it makes sense to ascribe only to the animal as a whole” (Bennett and Hacker 2003 p 240). The authors are not alone in taking this view, and the hunt for the neural correlates of consciousness is based on the premise that such a distinction will be found but so far there is no agreement about whether it has or will be.
The same can be said of the Integration Consensus. Claiming that the function of consciousness is integration, they say “consciousness serves an essential, integrative role for the somatic nervous system” (p 53) and “consciousness integrates neural activities and information-processing structures that would otherwise be independent” (p 11). I want to ask not only how subjective experience can be said to integrate objective activities and structures (implying a version of the hard problem or possibly some kind of unexplained downward causation) but, more fundamentally, why these activities and structures need something extra to integrate them. Are they not integrated by structural connections or by the various processes proposed to account for binding (Cleeremans 2003). Contrary to their claim, there is no consensus over integration either.
The confusion is clearest in their discussion of Global Workspace Theory (GWT). They cite over twenty papers and books as evidence for this consensus but include in this list authors who hold totally opposed interpretations of GWT. These too can be divided into two main camps. On the one hand is a loosely Cartesian materialist or implicitly dualist account like the one proposed here. According to this, and Baars’ (1988) original formulation, information (or processes, percepts, thoughts etc.) compete for access to the GW where they “become conscious” and are broadcast to the rest of the unconscious audience. This interpretation retains the hard problem and all the difficulties of Cartesian materialism.
A completely different interpretation is more common (though not universal) in neuronal global workspace theory (Dehaene and Naccache 2001) and means that no process or information has to ‘become conscious’ or ‘enter consciousness’. As Dehaene (2009) explains, brain-scale broadcasting creates the possibility of verbal and other types of report and this is experienced as a conscious state. There is no additional consciousness or subjectivity. This is what Dennett (2005), more colourfully, calls ‘fame in the brain’ or ‘cerebral celebrity’. Fame is not something additional to being widely known, nor is consciousness something additional to being widely broadcast. On this interpretation of GWT there is no dualism or hard problem. These views are deeply opposed and there is no consensus as to which is correct.
In summary, this paper proposes an implicitly dualist or Cartesian materialist theory of consciousness without citing the many well-known problems with such theories and claiming consensus where none exists. Their discussion of olfaction is a helpful and interesting addition to our understanding but their theory of the function of consciousness does not stand up to scrutiny.
Baars, B.J. (1988) A Cognitive Theory of Consciousness. Cambridge, Cambridge University Press
Bennett, M.R. & Hacker, P. M. S. (2003). Philosophical foundations of neuroscience. Blackwell Publishing.
Blackmore, S. (2011) Consciousness: An Introduction, New York, Oxford University Press and (2010) London, Hodder
Chalmers, D. (1995) Facing up to the problem of consciousness. Journal of Consciousness Studies,2:3, 200-219
Cleeremans, A. E. (2003). The unity of consciousness: Binding, integration, and dissociation. Oxford University Press.
Dehaene, S. (2009) Neuronal global workspace. In Bayne, T., Cleeremans, A. and Wilken, P. (2009) The Oxford Companion to Consciousness, Oxford, Oxford University Press
Dehaene, S. and Naccache, L. (2001) Towards a cognitive neuroscience of consciousness: basic evidence and a workspace framework, Cognition, 79, 1-37
Dennett, D.C. (1991) Consciousness Explained. Boston, MA, and London; Little, Brown and Co.
Dennett, D. (2005) Sweet Dreams Cambridge, Mass, MIT Press
Jackson, F. (1982) Epiphenomenal qualia, Philosophical Quarterly, 32, 127-136