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For some years now I have argued that when it comes to explaining the existence of consciousness (subjective self-awareness), materialists have nothing interesting to say, that their so-called explanation amounts to nothing more than “poof! It happened.” See here, here and here. I was gratified to learn in a recent exchange that Elizabeth Liddle agrees with me at least at a certain level. In various places in that exchange she wrote:
Certainly an emergent property must be explained in terms of the system; and clearly an explanation must be “systematic” in the sense of specifying a cascade of mechanisms. . . .
“[Emergent” is] simply a word to denote the idea that when a whole has properties of a whole that are not possessed by the parts, those properties “emerge” from interactions between the parts (and of course between the whole and its environment). It is not itself an explanation – to be an explanation you would have to provide a putative mechanism by which those properties were generated. . . .
So the claim that consciousness is an emergent property of the materials of our bodies is not an explanation – it’s a conjecture. “[I]t’s emergent” would be [on an intellectual par with saying “It’s magic!”]. To support an emergent hypothesis you would have to provide a description of the putative processes by which the property emerges. So I agree with that.
In this respect Liddle apparently agrees with Thomas Nagel: “Merely to identify a cause [of consciousness] is not to provide a significant explanation, without some understanding of why the cause produces the effect.” Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False
For Nagel, to qualify as a genuine explanation, an emergent account would make the connection between mental events such as subjective self-awareness and the electro-chemical state of the nervous system “cease to seem like a gigantic set of inexplicable correlations and would instead make it begin to seem intelligible.” Nagel concedes, however, that at this point a systematic theory of consciousness is “a complete fantasy.”
I agree with Nagel. Science has not come remotely close to explaining how a physical event (the electro-chemical processes in the brain) can result in mental events (e.g., qualia; subjective self-awareness; intentionality; subject-object duality, etc.).
Liddle disagrees. She says that scientists have in fact identified how physical events result in mental events and she repeatedly directed us specifically to the work of Edelman and Tononi in A Universe Of Consciousness: How Matter Becomes Imagination. She gives a faint sketch of Edelman/Tononi’s argument:
But I think the essence of the answer lies in our capacity to simulate the outputs of our actions before we execute them and feedback those outputs as inputs into the action-selecting process. That allows us to both anticipate and remember in what Edelman calls a “remembered present”, in which past and possible futures are integrated.
At Liddle’s behest, I have read A Universe Of Consciousness. The authors summarize their key conclusion as follows:
Memory is a central component of the brain mechanisms that lead to consciousness. . . . the key conclusion is that whatever its form, memory itself is a system property. It cannot be equated exclusively with circuitry, with synaptic changes, with biochemistry, with value constraints, or with behavioral dynamics. Instead, it is the dynamic result of the interactions of all these factors acting together, serving to select an output that repeats a performance or an act.
As anyone with any experience in this area would have suspected, Edelman and Tononi identify consciousness as an emergent property. But, according to Liddle, they have gone a step further and identified at least some of the details of how consciousness arose from chemicals. Could this really be the case? Thomas Nagel has been among the most famous and influential philosophers of mind since the early 70’s. He says that a systematic theory of consciousness is “a complete fantasy.” Does Elizabeth Liddle know something that Nagel doesn’t?
You will probably not be surprised to learn that the answer to that question is “no.” But don’t take my word for it. In his review of A Universe Of Consciousness for Nature, Raymond J. Dolan wrote: “Explaining consciousness has become the Holy Grail of modern neuroscience. Any reckoning on who has found the true path is surely premature.”
In his review for The Guardian Steven Poole wrote:
Few people these days seriously doubt that consciousness arises solely from physical activity inside our skulls. But the big question is how this happens. Why does matter arranged in this way, and not others, give rise to minds? This is a question that Gerard Edelman and Giulio Tononi signally fail to answer, despite the grand promise of their subtitle.
Where has Liddle gone wrong? I can give no better answer than UD commenter Box, who wrote in that same exchange:
The book doesn’t help you at all, it’s a classic example of the good old cum hoc ergo propter hoc – ‘correlation is causation fallacy’. Evidence is provided suggestive of consciousness being *associated* with interconnected regions of the brain. And from this, Edelman and Tononi conclude that consciousness *arises* from the brain. IOW no mechanism that describes how to get from chemicals to consciousness, but a questionable cause logical fallacy instead.
In other words, Edelman and Tononi have asserted as an explanation exactly what Nagel said does not count as a genuine explanation – a gigantic set of inexplicable correlations.
The issue here is really very very simple. And for that reason I am always amazed when highly educated and articulate people like Liddle utterly fail to grasp it. I will try one more time to lay it out step by step.
1. Merely identifying a putative cause is not an explanation.
2. To count as an explanation, one must also give some understanding of why the putative cause produces the effect.
3. Asserting that physical brain state “A” exists (whatever “A” happens to be) and consciousness exists merely identifies a correlation.
4. For physical brain state A to count as an explanation of consciousness, one must also provide an understanding of why that physical event gave rise to that mental event.
5. This has never been done; no one has come close to doing it. There is good reason to believe it is not, in principle, possible to do it.