Consciousness

• seCtIon tWo: tHe BRAIn
  in the microtubules). If quantum computing does occur in the brain, this is very
  important, but it only adds another layer of complexity to the way the brain
  works. If there is a hard problem, it might be rephrased here as ‘How does subjec-
  tive experience arise from objective reduction in the microtubules?’ The strange
  effects entailed in quantum processes do not, of themselves, have anything to
  say about the experience of light or space or pain or the colour of the traffic light.
  They do not explain why there is experience rather than no experience. American
  philosopher Jesse Prinz refers to ‘those pesky quantum phenomena that are a
  refuge for non-mysterians with an appetite for the mysterious’ (2003, p. 116). Koch
  and Hepp (2006/2007; here in preprint [2007], p. 1) call the connection between
  quantum mechanics and consciousness an ‘entertaining topic at parties’ but
  argue that evidence from biophysics and computational neuroscience makes any
  connection unlikely. Samanta Pino and Ernesto Di Mauro (peer commentary on
  Hameroff and Penrose, 2014, here p. 92) wonder whether the lack of alternative
  explanations may be making quantum physics seem more promising than it
  should for tackling the ‘intricately unapproachable’ unknown that is conscious-
  ness. And Pat Churchland concludes that ‘Pixie dust in the synapses is about as
  explanatorily powerful as quantum coherence in the microtubules’ (1998, p. 121).
  But the theory may at least have the benefit of pushing us closer towards a need
  for ‘falsifiable verification’, Pino and Di Mauro concede (p. 92); and Hameroff and
  Penrose respond confidently that the proposed form of objective reduction ‘may
  be fairly close to either experimental confirmation or refutation’ (p. 99). So, quan-
  tum processing may yet turn out to be the solution to the hard problem, but so far
  it seems mainly to have moved the problem into a microtubule-shaped theatre.

MULTIPLE DRAFTS

The most concerted attempt to ditch the theatre is probably Dennett’s multiple

drafts theory, which he proposed as an alternative to Cartesian materialism.

‘When you discard Cartesian dualism’, Dennett says,

you really must discard the show that would have gone on in the

Cartesian Theatre, and the audience as well, for neither the show nor the

audience is to be found in the brain, and the brain is the only real place

there is to look for them.

(1991, p. 134)

This wholesale rejection of the idea of ‘me’ can be deeply unsettling. So much

so that Dennett has even been called ‘the Devil’, his ideas needing ‘an exorcism,

aimed at eliminating the spectre of materialist reductionism from the science of

consciousness’ (Voorhees, 2000, p. 55).

In multiple drafts theory, perceptions, emotions, thoughts, and all kinds of cog-

nitive activity are accomplished in the brain by multitrack parallel processes that

interpret and elaborate sensory inputs, and all are under continuous revision.

Like the many drafts of a book or article, perceptions and thoughts are constantly

revised and altered, and at any point in time there are multiple drafts of narrative

fragments at various stages of editing in various places in the brain.

You may then want to ask, ‘but which ones are conscious?’ If you do so, you are

imagining a Cartesian theatre in which only some of these drafts are re-presented

‘Pixie dust in the

synapses is about as

explanatorily powerful

as quantum coherence

in the microtubules’

(Churchland, 1998, p. 121)

‘Daniel Dennett is the

Devil’

(Voorhees, 2000, pp. 55–56)