Dennett's Indeterminism Challenge
A contribution to Daniel Dennett's Fall 2010Dan Dennett challenged me to give reasons why quantum indeterminacy is better than computer pseudo-randomness. Dennett does not deny quantum indeterminacy. He just doubts that quantum randomness is necessary for free will. I think it breaks the causal chain of pre-determinism. Quantum randomness has been available to evolving species for billions of years before pseudo-randomness emerges with humans. But Dennett does not think, as does Jacques Monod, for example, that quantum indeterminacy is necessary for biological evolution. The evolved virtual creatures of computer-based artificial life programs demonstrate for Dennett that biological evolution is an algorithmic computational process. Here I propose five cases where quantum chance is critically important and more fundamental than a computer's pseudo-randomness. They all share a basic insight from information physics. Whenever a stable new information structure is created, two things must happen. The first is a collapse of the quantum wave function that allows one or more particles to combine in the new structure. The second is the transfer away from the structure to the cosmic background of the entropy required by the second law of thermodynamics to balance the local increase in negative entropy (information).
Seminar on Free Will at Tufts University
Laplace’s DemonIndeterministic events are unpredictable. Consequently, if any such probabilistic events occur, as Dennett admits, Laplace's Demon cannot predict the future. Information cosmology provides a second reason why such a demon is impossible. There was little or no information at the start of the universe. There is a great deal today, and more being created every day. There is not enough information in the past to determine the present, let alone completely determine the future. Creating future information requires quantum events, which are inherently indeterministic. The future is only probable, though it may be "adequately determined." Since there is not enough information available at any moment to comprehend all the information that will exist in the future, Laplace demons are impossible.
Intelligent DesignersSuppose that determinism is true, and that the chance driving spontaneous variation of the gene pool is merely epistemic (human ignorance), so that a deterministic algorithmic process is driving evolution. Gregory Chaitin has shown that the amount of information (and thus the true randomness) in a sequence of random numbers is no more than that in the algorithm that generates them. This makes the process more comprehensible for a supernatural intelligent designer. And it makes the idea of an intelligent designer, deterministically controlling evolution with complete foreknowledge, more plausible. This is unfortunate. An intelligent designer with a big enough computer could reverse engineer and alter the algorithm behind the pseudo-randomness driving evolution. This is just what genetic engineers do. But cosmic rays, which are inherently indeterministic quantum events, damage the DNA to produce genetic mutations, variations in the gene pool. No intelligent designer could control such evolution. So genetic engineers are intelligent designers, but they cannot control the whole of evolution.
Frankfurt controllersFor almost fifty years, compatibilists have used Frankfurt-style Cases to show that alternative possibilities are not required for freedom of action and moral responsibility. Bob Kane showed in 1985 that, if a choice is undetermined, the Frankfurt controller cannot tell until the choice is made whether the agent will do A or do otherwise. Compatibilists were begging the question by assuming a deterministic connection between a “prior sign” of a decision and the decision itself. More fundamentally, information philosophy tells us that because chance (quantum randomness) helps generate the alternate possibilities, information about the choice does not come into the universe until the choice has been made. Either way, the controller would have to intervene before the choice, in which case it is the controller that is responsible for the decision. Frankfurt Controllers do not exist.
Dennett EavesdroppersI call this Dennett's Eavesdropper because, in a discussion of quantum cryptography, Dennett agrees there is a strong reason to prefer quantum randomness to pseudo-randomness for encrypting secure messages. He sees that if a pseudo-random number sequence were used, a clever eavesdropper might discover the algorithm behind it and thus be able to decode the message. Quantum cryptography and quantum computing use the non-local properties of entangled quantum particles. Non-locality shows up when the wave-function of a two-particle system collapses and new information comes into the universe. See the Einstein-Podolsky-Rosen experiment.
Meme MakersRichard Dawkin’s unit of cultural information has the same limits as purely physical information. Claude Shannon’s mathematical theory of the communication of information says that information is not new without probabilistic surprises. Quantum physics is the ultimate source of that probability and the possibilities that surprise us. If the result were not truly unpredictable, it would be implicitly present in the information we already have. A new meme, like Dennett’s intuition pumps, skyhooks, and cranes, would have been already predictable there in the past and not his very original creations. Dennett creates new information. He is a meme maker!
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