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September 14 - September 23, 2018
A characteristic feature of conscious thought (at least when one is in a normal psychological state, and not the subject of a ‘split-brain’ operation!) is its ‘oneness’ – as opposed to a great many independent activities going on at once.
there could conceivably be some relation between this ‘oneness’ of consciousness and quantum parallelism. Recall that, according to quantum theory, different alternatives at the quantum level are allowed to coexist in linear superposition! Thus, a single quantum state could in principle consist of a large number of different activities, all occurring simultaneously.
If a conscious ‘mental state’ might in some way be akin to a quantum state, then some form of ‘oneness’ or globality of thought might seem more appropriate than would be the case for an ordinary parallel computer.
Experiments with toads have shown that under suitable conditions, a single photon impinging on the dark-adapted retina can be sufficient to trigger a macroscopic nerve signal
The same appears to be true of man (Hecht, Shlaer, and Pirenne 1941), but in this case there is an additional mechanism present which suppresses such weak signals, so that they do not confuse the perceived picture with too much visual ‘noise’.
Since there are neurons in the human body that can be triggered by single quantum events, is it not reasonable to ask whether cells of this kind might be found somewhere in the main part of the human brain?
One might speculate, however, that somewhere deep in the brain, cells are to be found of single quantum sensitivity. If this proves to be the case, then quantum mechanics will be significantly involved in brain activity.
a nerve signal creates a detectable changing electric field in its surroundings (a toroidal field, with the nerve as axis, and moving along the nerve). This field could disturb the surroundings significantly, and the one-graviton criterion might be easily met within these surroundings.
we do speculate that single-quantum-sensitive neurons are playing an important role deep inside the brain, we can ask what effects these might have.
quantum computers cannot be used to perform non-algorithmic operations (i.e. things beyond the power of a Turing machine), but can, in certain very contrived situations, achieve a greater speed,
I wish to return to an issue that has been an underlying theme of much of this book. Is our picture of a world governed by the rules of classical and quantum theory, as these rules are presently understood, really adequate for the description of brains and minds?
Is the brain to be regarded as ‘observing itself’ whenever a thought or perception emerges into conscious awareness?
modern electronic computers, the existence of discrete states is needed (say, coding the digits 0 and 1), so that it becomes a clear-cut matter when the computer is in one of these states and when in another.
This is the very essence of the ‘digital’ nature of computer operation.
At least with computers we know that this action is algorithmic (by our design!), and we do not try to harness any putative non-algorithmic behaviour in physical laws. But with brains and minds the situation is, I maintain, very different. A plausible case can be made that there is an essential non-algorithmic ingredient to (conscious) thought processes.
IN DISCUSSIONS OF the mind–body problem, there are two separate issues on which attention is commonly focused: ‘How is it that a material object (a brain) can actually evoke consciousness?’; and, conversely; ‘How is it that a consciousness, by the action of its will, can actually influence the (apparently physically determined) motion of material objects?’
My question is: ‘What selective advantage does a consciousness confer on those who actually possess it?’
one might believe that consciousness is merely a passive concomitant of the possession of a sufficiently elaborate control system and does not, in itself, actually ‘do’ anything. (This last would presumably be the view of the strong-AI supporters, for example.)
am prepared to believe that consciousness is a matter of degree and not simply something that is either there or not there. I take the word ‘consciousness’ to be essentially synonymous with ‘awareness’
In my own way of looking at things, the question of intelligence is a subsidiary one to that of consciousness. I do not think that I would believe that true intelligence could be actually present unless accompanied by consciousness.
On the other hand, if it does turn out that the AI people are eventually able to simulate intelligence without consciousness being present,
there must be an essentially non-algorithmic ingredient in the action of consciousness.
there is no generally accepted criterion for the manifestation of consciousness. It still might be that there is a hallmark of conscious behaviour, but one not universally recognized.
there must indeed be some mode of behaviour which is characteristic of consciousness (even though not always evidenced by consciousness), which we are sensitive to through our ‘common-sense intuitions’. Second, consider the ruthless process of natural selection.
not all of the activity of the brain is directly accessible to consciousness. Indeed, the ‘older’ cerebellum – with its vast superiority in local density of neurons – seems to carry out very complex actions without consciousness being directly involved at all.
Moreover, there is a simple ‘bottom line’ reason for believing that consciousness must have some active effect, even if this effect is not one of selective advantage.
It seems to me to be clear that the musings and mutterings that we indulge in, when we (perhaps temporarily) become philosophers, are not things that are in themselves selected for, but are the necessary ‘baggage’ (from the point of view of natural selection) that must be carried by beings who indeed are conscious, and whose consciousness has been selected by natural selection,
One view that I have heard expressed is that awareness might be of an advantage to a predator in trying to guess what its prey would be likely to do next by ‘putting itself in the place’ of that prey.
Of course, it is difficult to see how the random procedures of natural selection could have been clever enough to give an automaton predator a complete copy of the prey’s program. This would sound more like espionage than natural selection!
The idea alluded to above seems to relate to a point of view about consciousness that one often hears put forward, namely that a system would be ‘aware’ of something if it has a model of that thing within itself, and that it becomes ‘self-aware’ when it has a model of itself within itself.
What is it that we can do with conscious thought that cannot be done unconsciously? The problem is made more elusive by the fact that anything that we do seem originally to require consciousness for appears also to be able to be learnt and then later carried out unconsciously (perhaps by the cerebellum). Somehow, consciousness is needed in order to handle situations where we have to form new judgements, and where the rules have not been laid down beforehand. It
many unconscious factors enter into our conscious judgements: experience, intuition, prejudice, even our normal use of logic. But the judgements themselves, I would claim, are the manifestations of the action of consciousness.
My own line of reasoning has been that unconscious processes could well be algorithmic, but at a very complicated level that is monstrously difficult to disentangle in detail. The fully conscious thinking that can be rationalized as something entirely logical can again (often) be formalized as something algorithmic, but this is at an entirely different level.
The judgement-forming that I am claiming is the hallmark of consciousness is itself something that the AI people would have no concept of how to program on a computer.
there seems to be something non-algorithmic about our conscious thinking. In particular, a conclusion from the argument in Chapter 4, particularly concerning Gödel’s theorem, was that, at least in mathematics, conscious contemplation can sometimes enable one to ascertain the truth of a statement in a way that no algorithm could.
One needs external insights in order to decide the validity or otherwise of an algorithm (more about this later). I am putting forward the argument here that it is this ability to divine (or ‘intuit’) truth from falsity (and beauty from ugliness!), in appropriate circumstances, that is the hallmark of consciousness.
Unsupervised machine learning?
Are we all feeding these external criteria with Google, Facebook and others?
Is that the real goal of these companies?
Enough information is in principle available for the relevant judgement to be made, but the process of formulating the appropriate judgement, by extracting what is needed from the morass of data, may be something for which no clear algorithmic process exists – or even where there is one, it may not be a practical one.
am guessing that consciousness would, under such circumstances, come into its own as a means of conjuring up the appropriate judgements.
once one has done a large number of similar problems, the decision as to whether to multiply or divide the numbers may become second nature and can be carried out algorithmically – perhaps by the cerebellum.
At that stage, awareness is no longer necessary, and it becomes safe to allow one’s conscious mind to wander and to contemplate other matters – although, from time to time one may need to check that the algorithm has not been sidetracked in some (perhaps subtle) way.
do not see how natural selection, in itself, can evolve algorithms which could have the kind of conscious judgements of the validity of other algorithms that we seem to have.
In order to decide whether or not an algorithm will actually work, one needs insights, not just another algorithm.
is not easy to ascertain what an algorithm actually is, simply by examining its output.
Moreover, the slightest ‘mutation’ of an algorithm (say a slight change in a Turing machine specification, or in its input tape) would tend to render it totally useless, and it is hard to see how actual improvements in algorithms could ever arise in this random way. (Even deliberate improvements are difficult without ‘meanings’ being available.
We are back with the problem of what consciousness actually is, and what it can actually do that unconscious objects are incapable of – and how on earth natural selection has been clever enough to evolve that most remarkable of qualities.
should point out that the terms ‘algorithm’ and ‘algorithmic’ refer to anything that (in effect) can be simulated on a general-purpose computer.
My impression is that the strong conviction of the validity of a flash of inspiration (not 100 per cent reliable, I should add, but at least far more reliable than just chance) is very closely bound up with its aesthetic qualities.
It is these judgements that I consider to be the hallmark of conscious thinking. My guess is that even with the sudden flash of insight, apparently produced ready-made by the unconscious mind, it is consciousness that is the arbiter, and the idea would be quickly rejected and forgotten if it did not ‘ring true’.
In relation to this, the question of what constitutes genuine originality should be raised. It seems to me that there are two factors involved, namely a ‘putting-up’ and a ‘shooting-down’ process. I imagine that the putting-up could be largely unconscious and the shooting-down largely conscious. Without an effective putting-up process, one would have no new ideas at all.
