We are all critics and all cranks. Some just get a wider audience. Richard Muller, distinguished professor of physics at Berkeley, recounts a good deal of his pathbreaking research in his latest book, as well as roles in founding and inspiring the work of others, some of which / whom went on to win Nobel prizes. Along the way, he provides a high level and very pleasant introduction to the highlights of twentieth century physics. But he can't seem to resist going down some very personal tangents as well, like free will, Richard Dawkins, and a profession of faith.
His views on time are obviously the theme of the book, and the tease as well. He keeps the meat of the matter till the last few pages. To put it most simply, he dismisses the common idea that the progression of time in the universe is connected to the increase of entropy that is expressed in the second law of thermodynamics. Instead, he proposes that time, having been created with the advent of the big bang, as was space itself, represents the continual expansion of that four-dimensional construct that is our universe. Thus we all exist in a "now" that is the bleeding edge of cosmic 4-D expansion, just as space itself is continually expanding. Looking outward at anything, however close or far, is always looking back in time into areas of the universe that have already happened. And just as there is no center or edge to the expansion of space, there is also no edge to the progression of time- all points in space progress through "now", leaving aside the relativistic oddities of some "nows" getting slowed down by relative spatial or gravitational acceleration.
I find this idea very attractive. It is far more sensible than the entropy idea, and probably the best thing going, until we gain a deeper understanding of the mysteries of cosmic origins, the structure of space, and of quantum physics in particular. The latter still resists both unification with other aspects of physics and, frankly, common sense. Yet this edge-of-the-big-bang is far from a theory- it is just a hunch, with minimal predictions, the main one of which is that time might be accelerating along with the accelerating expansion of the universe, if space and time happen to be linked in that way.
However, when it comes to amateur philosophy, the book makes a good deal less sense. Muller spends an effective few chapters on the limits of science and philosophical physicalism- the great deal that we don't know, and perhaps can't know. The nature of the origin of the big bang, given that it originated both the time and space that we are familiar with, is surely one. The various mysteries of quantum physics are others. But some of his other suggested limits edge into very questionable territory.
Combined with other known limits, like the indeterminacy of quantum mechanics, and Gödel's theorems of incompleteness, we end up with large areas of reality that are essentially unknowable, at least in a scientific sense. One of these is the future. Because of quantum indeterminacy, as well as chaos theory, physics turns out to not be deterministic as the classical physicists had believed since the time of Newton. This provides, in Muller's eyes, openings for things like qualia, free will and souls.
There is a long discussion of the "what it is like to see red" question, featuring Mary, who is raised in a grey world but knows didactically everything there is to know about color vision. When she first sees color as a mature adult, does she learn anything new? Muller's answer is yes, and he takes that as an intrinsic limit on human knowledge.
The whole qualia question, which is what the "seeing red" exercise is about, seems to me to say much less than Muller and others think. He believes that it points to something beyond our physical constitution that characterizes us- a soul. For the same reason, he claims that he would not want to be transported à la Star Trek, for even if his physical body were reconstituted down to the smallest detail, he might not end up being "himself". Again, a non-material soul lies at the bottom of this, which he explicitly claims, even though he is doubtful whether it survives death:
"When I see blue, do you see blue? That is not a scientific question. Does that make it invalid? This issue is related to the difference between the brain and the mind. Is there something beyond the brain, something behind the circuitry, something more than the physical, mechanical set of atoms, something that can not only see, but knows what a color looks like? I can't prove to you that such knowledge exists. I can only attempt to pursuade you."
To me, there seems to be no reason whatsoever to propose anything beyond the physical mechanism to account for all this. We can grant that subjective experience is utterly different from didactic knowledge. That is intrinsic to beings with consciousness and experiences, and is covered by a difference of perspective. I, looking into your brain, will never have the experiences that you are having subjectively via that brain. It is like expecting someone reading the computer code behind World of Warcraft to experience gaining powers and making alliances. That supposition is a simple, but profound, category error.
Should we care about so much (subjective) knowledge and experience going up in smoke every second and every lifetime? Surely it is a tragedy, which we try to remedy by sharing subjectivity via conversation, writing, the arts, and other ways. But the fact that, being perspectivally enclosed, it is beyond science (certainly with current technologies) means neither that it is an illusion, nor that its reality is somehow "beyond the physical". Its complete dependence on the physical is clear from the biology of stroke, dementia, development, mental time delays, and innumerable other phenomena.
The wonderfulness of its construction, and its tendency to lull us into flights of subjective omnipotence or is no excuse for not taking the biology seriously. This is true even if one appreciates that physics (let alone biology) can not explain, or even represent, everything. There are many things that they can still properly explain, and many things that they put very tight boundaries on even if complete explanations are not yet available.
But there is more...
"There is a spiritual world separate from the real world. Wave functions from the two worlds are entangled, but since the spiritual world is not amenable to physical measurement, the entanglement can't be detected. Spirit can affect physical behavior- I can choose to build or smash a teacup; I can choose to make war or seek peace- through what I call free will."
"It is remarkable how often you run into the phrase "Science says..." to support an idea that actually has no foundation in science. It is often physicalism in disguise "Science says we have no free will." Nonsense. That statemen is inspired by physics, but it has no justification in physics. We can't predict when an atom will disintegrate, and the laws of physics, as they currently exist, say that this failure is fundamental. If we can't predict such a simple physical phenomenon, then how can we imagine that someday we will be able to show that human behavior is completely deterministic?"
The weakest aspect of the book is its numerous discussions of free will. Muller seems to have a particularly unexamined notion of it. He cites quantum indeterminacy as providing an opening for free will, since it means that the universe is not determined. But how does randomness and indeterminate-ness help the cause? How does our ability to make choices and affect the flow of events relate to reality's constitutive randomness? An inability to predict or compute the future does not imply that our physical mechanism can not and does not make choices, including meaningful ones. For example, computers make choices all the time, and increasingly sophisticated, random-event influenced, and, to us, unintelligible ones.
If everything were determined, that would not even affect our sensation of free will. That is the Greek tragedy, where key events are pre-ordained, but still the actors feel themselves to be acting meaningfully, until the end when the hand of fate is revealed to all. Even such slim (and fictional) concessions to fate are out of the question when the future is truly unknown due to all the physical principles Muller cites.
But determined or not, it is not clear what this free will really is. In the worst-case scenario, everything is determined, and we can also predict the future- a future that we can do nothing to change, because everything up to that point as been determined as well. But how would that really feel? I think it would still feel as though we had free will, since we would have reasons for doing what we are going to do, which feel compelling, leading to exactly the actions that we are taking, predicted or not.
I think the secret is that free will is, particularly here in Muller's book, but also more generally, a code word for "soul". It is another, and even more vague, way to make claims for a non-physical entity that lies behind our most important actions and deepest feelings. The intuition is that mere mechanism can not conjure the sovereignity of choice, and is somehow separate from the all-important "I", whose immateriality and freedom are so intutively self-evident.
"Am I simply a wood chip caught in a complicated machine, bouncing around as the gears turn, confusing my rapid action with my importance?"
Why an eminent physicist feels the need to posit special, extra-scientific hypotheses around the issue of consciousness is truly unfortunate. His inability to explain the big bang does not prompt similar flights of intuition unbound, yet his lack of knowledge about biology and inability to bridge the far more modest conceptual gap between subjective consciousness and what we know scientifically (exemplified by the qualia/Mary exercise) does. It is ironic that intuition is so particularly susceptible to error and inflation when trying to analyze itself.
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