This is an addendum to this post: Beautiful Analogue of Quantum Mechanical Phenomena, concerning the comments John H. Conway makes at 9 minutes 12 seconds on free-will versus determinism, as it seems to be commonly understood by physicists. But physicists tend to rather oversimplify these issues. Here's Jade explaining how this happens. What physicists typically forget, whilst considering this question of physical determinism, is that the possibility of making predictions about the evolution of a deterministic physical system only meaningfully applies when the prediction and the measurements any such prediction needs to be effective, only exist outside the system which is the subject of the prediction.
The reason is simply that the existence of the physical representation of the prediction, if it were itself a part of the system the evolution of which it was supposed to predict, would be effectively a diagonalisation of the prediction. This is the idea Alan Turing was exploring in his famous computability paper of 1935. Here's Jade again, on mathematics and computation:
See also this talk by Carlo Rovelli, at 9 minutes 43 seconds, where he coins a new term totology to describe the study of the Universe as a whole system.
Now, when we think about free will, what we are really asking is "What is the sense in which I feel that I am responsible or my own actions in the world around me?" and "What is the difference between whatever this conscious awareness ultimately is, and mere computation which is nothing much more than a conscious interpretation of the physical configuration of a part of the world (i.e. the computer) as something which represents the result of some physical (i.e. mechanical and therefore deterministic) computational process?"
As Jade points out, the crucial difference is that consciousness is produced as an emergent phenomenon of particular physical systems, those ones which we call animals, although it seems quite possible that plants too may have a degree of consciousness. Note that in Jade's view, consciousness is not a property of any individual parts of which a conscious system is composed, rather that it is an irreducible property of whole systems. But not just any whole system, only perfectly functioning conscious systems. So the connection with free will is when we realise that our sense of being personally, individually responsible for our own actions is acutely dependent on our experience of interacting with the world around us, and what makes us feel that we are conscious agents, capable of deliberately acting on the world around us, is our belief that conscious states of mind are physically real, and have observable effects on the physical world, in just the same way that the properties of a droplet of water, for example its ability to focus incident sunlight on a certain point, is a physically real phenomena, about which we can construct mathematical models which accurately predict the effects certain conditions are likely to have on the droplet.
Now compare Jade's explanation of the issues with that of Professor Sir Roger Penrose, FRS etc. etc.
Penrose, on noting that Turing's paper proves that there are certain problems which classical computers cannot solve, concludes that there must be something special in the human nervous system which is somehow essentially "quantum", and that it is this quantumness of certain particular parts of the neurons in actual physical human brains which makes them capable of producing conscious awareness. And he doesn't mention it here, but in his book The Emperor's New Mind, he puts forward the thesis that it is this quantum awareness which is responsible for human being's superior abilities at solving mathematical conundra, like the actual existence of superpositions of quantum consciousness, I suppose? 😂 [See this talk by Rovelli, at 34 minutes 46 seconds.]
There is another, different possibilty, which is that the limits of classical computers are not in fact real, but that the halting problem results from a misconception about what a computable function actually is. See this short note I wrote in 2012 to explain what I mean, with an earlier, longer version, including a section on Gödel's First Incompleteness Theorem.
Penrose's book, mentioned above, starts with a story about a little boy who was a computer geek, and this kid felt he knew so much about computers that he knew how it must actually feel to be a computer! I often wonder if that kid was supposed to be a representation of me. If so, it was not a very accurate representation.
The Daemon, in Aristotle, is Gaia, Mother Earth:
And here is some good advice about how to live with your mind!
This post has a sound-track: London Grammar - Hell to the Liars.
See also this talk by Carlo Rovelli, at 9 minutes 43 seconds, where he coins a new term totology to describe the study of the Universe as a whole system.
Now, when we think about free will, what we are really asking is "What is the sense in which I feel that I am responsible or my own actions in the world around me?" and "What is the difference between whatever this conscious awareness ultimately is, and mere computation which is nothing much more than a conscious interpretation of the physical configuration of a part of the world (i.e. the computer) as something which represents the result of some physical (i.e. mechanical and therefore deterministic) computational process?"
As Jade points out, the crucial difference is that consciousness is produced as an emergent phenomenon of particular physical systems, those ones which we call animals, although it seems quite possible that plants too may have a degree of consciousness. Note that in Jade's view, consciousness is not a property of any individual parts of which a conscious system is composed, rather that it is an irreducible property of whole systems. But not just any whole system, only perfectly functioning conscious systems. So the connection with free will is when we realise that our sense of being personally, individually responsible for our own actions is acutely dependent on our experience of interacting with the world around us, and what makes us feel that we are conscious agents, capable of deliberately acting on the world around us, is our belief that conscious states of mind are physically real, and have observable effects on the physical world, in just the same way that the properties of a droplet of water, for example its ability to focus incident sunlight on a certain point, is a physically real phenomena, about which we can construct mathematical models which accurately predict the effects certain conditions are likely to have on the droplet.
Now compare Jade's explanation of the issues with that of Professor Sir Roger Penrose, FRS etc. etc.
Penrose, on noting that Turing's paper proves that there are certain problems which classical computers cannot solve, concludes that there must be something special in the human nervous system which is somehow essentially "quantum", and that it is this quantumness of certain particular parts of the neurons in actual physical human brains which makes them capable of producing conscious awareness. And he doesn't mention it here, but in his book The Emperor's New Mind, he puts forward the thesis that it is this quantum awareness which is responsible for human being's superior abilities at solving mathematical conundra, like the actual existence of superpositions of quantum consciousness, I suppose? 😂 [See this talk by Rovelli, at 34 minutes 46 seconds.]
There is another, different possibilty, which is that the limits of classical computers are not in fact real, but that the halting problem results from a misconception about what a computable function actually is. See this short note I wrote in 2012 to explain what I mean, with an earlier, longer version, including a section on Gödel's First Incompleteness Theorem.
Penrose's book, mentioned above, starts with a story about a little boy who was a computer geek, and this kid felt he knew so much about computers that he knew how it must actually feel to be a computer! I often wonder if that kid was supposed to be a representation of me. If so, it was not a very accurate representation.
The Daemon, in Aristotle, is Gaia, Mother Earth:
And here is some good advice about how to live with your mind!
This post has a sound-track: London Grammar - Hell to the Liars.
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