continued:
"1. I think the computing example with Word and Photoshop is a bit oversimplified."
- not sure why. It was Turing's genius to see that any application could be implemented by the same hardware, by changing its operating context; in this case, by loading different high level software. That software then determines the (data) ==> (output) relation.
"2. You mentioned "uncaused changes" at one point. Are you saying there is no such thing as randomness or do you accept that random outcomes can still be causal (just not deterministic)?"
- quantum physics tells us - if we believe the standard view - there is stuff out there which is neither causal nor deterministic. I find it strange that this fundamental discovery is still not accepted (at least implicitly) by many physicists today.
3. Regarding logic, one could argue that physics partly emerges from logic itself in which case it would not be particularly unusual to have higher-level logic dictating physical processes since, in some sense, logic may be even more fundamental and universal.
- I completely agree.
"4. Why can't multiple processes/paths lead to the same conclusion? I fail to see why this is a bad thing. (This question/comment refers to point D on pp. 5-6)."
- I'm not saying its a bad thing: on the contrary, it`s very positive because that is what underlies emergence of higher level entities that are independent of their lower level representations.
"5. You suggest that interactions are necessarily higher-level phenomena from particles themselves, but one could fairly easily argue that quantum field theory says that they are, in some sense, *more* fundamental than particles (or, at the very least, *as* fundamental)."
- well they arise from interactions of effective particles: however those arise.
"6. I'm still unconvinced by argument 6e on p. 7."
- I agree its debatable. But there is lots of evidence of the importance of random processes in microbiology and in brain microprocesses. It is a hypothesis that this might relate to quantum uncertainty. Needs development and testing.
"Finally, while I agree that there is most definitely some top-down causality in the universe, I tend to think that, in general, it tends to "drift" upward, if you will, i.e. if you were to model causal flow as a process, it would be like a random walk with drift with the drift going from the simple to the more complex."
- it starts off as a random walk, But then it is crucial that some outcomes of that random process get selected and others get rejected. It is that selection process (locally going against the grain of entropy growth) that underlies the growth of true complexity, and lifts causation from physical to biological. In physical terms, it is a non-unitary process, and it is not random: it is directed by the selection criteria. In biological terms, it is where useful information originates.
George
