On Wed, May 13, 2015 at 03:45:09PM +1000, Bruce Kellett wrote: > > That might be the idea. It is difficult to get to this, though, > since the notion of "primary materialism" doesn't really feature in > the argument. Before we get to the MGA, the dovetailer has been > introduced, and this is supposed to emulate the generalized brain > (even if the generalized brain is the whole galaxy or even the > entire universe) infinitely often, and the laws of physics emerge > from the statistics of all UD-computations passing through my actual > state. >
I can get it, but by an indirect route. Basically, the MGA shows a contradiction between computationalism and physical supervenience. But only for non-robust ontologies. For a robust ontology, counterfactuals are physically instantiated, therefore the MGA is invalid. Now physical supervenience has been demonstrated to a high level of empirical satisfaction. So we can conclude either that computationalism is falsified, or that our ontology is robust. But if the ontology is robust, UDA 1-7 demonstrates the reversal - physics depends only on the properties of the universal machine, not on any other ontological property of "primitive reality". Therefore we can excise the "physicalness" of ontology - anything capable of universal computation will do, such as arithmetic. But this chain of argument is not the usual one, so clearly it needs to be examined critically. Bruno has not given his imprimatur to it, dor example. Also, the MGA itself needs to shoring up, particularly with respect to the requirement of counterfactual correctness, and also that other issue I just raised about the recording player machinery changing the physical arrangement, perhaps by just enough to render physical supervenience toothless too. In which case the whole thing falls apart. -- ---------------------------------------------------------------------------- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics [email protected] University of New South Wales http://www.hpcoders.com.au ---------------------------------------------------------------------------- -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
