Thursday, 19 March 2015

Minsky's Solution to the Problem of Consciousness: Higher-Order Processes


There are philosophers and scientists who believe that “the problem of consciousness” is solved.

One example is Marvin Minsky.

Or, more specifically, in response to John Horgan's claim (in his The End of Science) that there are “those who doubted whether computers could be conscious”, Minsky claimed that “consciousness is a trivial issue”. Moreover, he said: “I've solved it, and I don't understand why people don't listen.” (184)

Minsky's definition of “consciousness” is very simple and very counter-intuitive. Or perhaps it seems that way simply because I've never really heard it before. That is, I've never heard anyone define consciousness is such a specific and peculiar manner.

Horgan says that Minsky's definition includes the idea that consciousness is “merely a type of short-term memory”. Minsky himself says that consciousness is a “low-grade system for keeping records”. And here's where Minsky's Artificial Intelligence comes in. Horgan says that

computer programmes such as LISP, which have features that allow their processing steps to be retraced” are, according to Minsky, 'extremely conscious'” (184).

Prima facie, in Minsky's account there are two things which are either being correlated with consciousness or which are being said to actually constitute consciousness: memory and what philosophers call “higher-order thoughts”.

It's clear that memory is certainly part of Minsky's picture. After all, he talks about “short-term memory” and “keeping records”.

In a sense, higher-order thoughts (or at least higher-order processes) tie in with the idea of memory in that memories can be about prior thoughts, processes and experiences.

So, yes, computers “keep records” of their previous computations or processes (as do humans). More specifically, programs such as LISP are said to “allow their processing steps to be retraced”. And that, according to Minsky, makes them “extremely conscious”.

The first response to this is to say that memory and higher-order processes are aspects of consciousness. They don't actually constitute consciousness.

In other words, is Minsky making a claim here of numerical identity (or definition)? Is he saying? -

consciousness = memory and higher-order processes (thoughts)

Again, higher-order processes are accompanied by consciousness or occur “within” consciousness. Acts of memory too are part of consciousness. Not consciousness itself.

It may indeed be the case that I'm getting bogged down with metaphors and analogies here in that phrases such as “processes are accompanied by consciousness” and “acts of memory are part of consciousness” may not be conceptually appropriate. They may not even make sense.

Nonetheless, there still seems to be something wrong with saying that consciousness simply is memory or higher-order processes (thoughts).

If we move away from computers here and concentrate on persons or human beings, this would be to say that introspection is consciousness. Many philosophers have indeed stressed the importance of introspection and indeed self-consciousness. Though I don't recall any who've said that introspection is consciousness. Again, I would say that introspection occurs within (forgive the spatial metaphor) consciousness or that it is an aspect of consciousness. Not that it is consciousness.

As for the words “self-consciousness”: that sort of gives the game away. It is, after all, meant to signify consciousness of the self. Thus there are two things: consciousness and the self. That means that self-conscious and consciousness can't be one and the same thing. Or, in other words, it is the self which is aware of consciousness or the self which is aware of the self. Again, the self is something given in (another spatial metaphor!) consciousness.


Quantum Dualism, Quantum Free Will & Quantum Consciousness


John Eccles's Quantum Free Will

Quantum mechanics is so sexy that it even explains free will and, therefore, mind-body dualism. Or at least John Eccles (who won the Noble Prize in 1963) thinks so.

This is how free will actually works and, up to a point, the account is completely scientific/biological in nature.

The first question is: How does the mind or self affect the brain?

Firstly, the story is about the brain itself. More specifically, the story is about how brain-cells fire.

Brain-cells fire “when charged molecules, or ions, accumulate at a synapse, causing it to release neurotransmitters” (John Horgan's The End of Science, page 173).

However, that accumulation of charged molecules (or ions) at the synapse doesn't automatically result in the release of neurotransmitters. It depends. What “triggers the firing of the neuron” depends on something else; not only on the accumulation of ions (molecules).

In this state of molecular accumulation, according to Eccles,

the ions exist in a quantum superposition of states; in some states the neuron discharges and in others it does not”.

Thus the mind/self must “exert its influence over the brain by 'deciding' which neuron will fire and which will not”.

If all this is utterly physical, can we talk about “deciding” at all? Is it the brain (or the neurons) which decides or the mind/self? Is all this tied to a conscious decision? Is it, indeed, a physical explanation of a mental decision? Indeed Is this a modern version of Descartes' pineal gland explanation of the mind-body problem/relationship?

Another way of putting all that is to ask this question:

Can all these physical things occur (i.e., the accumulation of ions at the synapse and even the “quantum superposition” of physical states) without bringing on board either the mind/self or the notion of a “decision”?

In other words, can we accept this quantum explanation and still leave the mind/self out of the picture? Or is this quantum story part of a theory which successfully explains the interaction of mind/self and brain? (In this case, the self/mind itself fires the neurotransmitters and that interaction itself can be explained in terms of a “quantum superposition” of physical states.)

Despite all that neuroscience (or physical theory), John Eccles still says: “We have no proof of any of this.” (173)

So perhaps what's truly motivating Eccles (as John Horgan suggests) is his aversion to what he calls “cheap materialism”. Indeed Eccles classes himself as a “religious person”. Moreover, he says that

the very nature of the mind is the same as the nature of life. It's a divine creation".

Roger Penrose's Quantum Consciousness



Whereas as quantum mechanics explains free will for John Eccles and Karl Popper, so it explains consciousness itself for Roger Penrose. In fact the two theories tie together in a vague kind of way.

For Eccles, quantum indeterminism (or the superposition of physical states at the synapses of a neurone) is explained by the “action” of the self or mind. With Penrose, the self is kept out of the picture; though quantum indeterminism is kept in.

More specifically,

Penrose conjectured that microtubules perform non-deterministic, quasi-quantum computations that somehow give rise to consciousness” (176).

What are microtubules? They're “minute tunnels of protein that serve as a kind of skeleton for most cells, including neurons” (176).

The obvious question is: Why do or would non-deterministic, quasi-quantum computations give rise to consciousness? Is it this argument again? -

i) Quantum indeterminacy is mysterious.

ii) Consciousness is mysterious.

iii) Therefore these things must be related?

Could it simply be that because there's no other answer at present that it's seen that this must be answer? If that were the case, then other outrageous things may be the answer too. Why is this quantum stuff more feasible than ghost stuff or outright dualism?