It was good to read in these letters between Bohm and Bub a sort of philosophy of science angle on modern science and philosophy theory. After reading these set of letters my advice would be to shift the emphasis from theory and the physical world to the concept of human understanding. What does it mean to understand the world around us? If we take the concept of human understanding in physics to mean what it meant for Galileo and Newton, i.e., representation in terms of a mechanical model, then physics parted company with human understanding following Newton's discovery of gravity and the very notion of action at a distance. Newton, according to Hume, showed the "imperfections of the mechanical philosophy and thereby restored Nature's secrets to that obscurity in which they ever did and ever will remain." Quite a statement from a philosopher of outstanding genius and one which, I think, should be taken very seriously. Some of the greatest physicists, including Bohm, have since echoed this insight in one way or another expressing their dissatisfaction with the nature of modern physics theories both at the micro level of QM and at the macro level of cosmology. For example, Dirac pointed out that leading physicists themselves understand that modern science no longer even tries to present models or pictures of how the world works. What they give us instead, according to Dirac, are ways of looking at the fundamental laws which make their self-consistency obvious. Dirac was no fool either. Neither was Bohm.

I'd say we're still only beginning the process of inquiry, with maybe billions of years of thinking and discovery ahead. So, being humble and recognizing our "place in time" is the correct approach. With 1 cm as 5000 years of thinking "completed", we've kilometres to go. It's also hubris to say we're the first to get this far, so we're just not typical as an intelligent technological species. Babes in the woods. Still, a complex picture has emerged, at least physically (physics), with many facts established that seem to be universal in Nature.

Every time I read something by Bohm et al regarding the foundations of QM my question is always the same: could an AI or "zombie" observer collapse a wave function? I know it's hard to test (impossible in the case of zombies) but it kind of gets at the heart of the matter, doesn't it? Since a machine apparently can (see the Quantum Zeno Experiment at the University of Texas, you would have to say yes. However since we don't know the basic meaning of "collapsing the wave function" in terms of how the model relates to reality, it doesn't get to the heart of anything. In QFT the quantum vacuum is a good model of abground and agrees with postmodern interpretations of reality as not constituted in a sustained manner, but only re-constituted as change. The neurological system being primarily an intra-action with abground, or the quantum vacuuum, looks like the most attractive approach for modeling how it produces an ontologically constituted experience of the real as already meaningful.

Incidentally Bohm's interpretation of quantum mechanics wasn't 'provocative' as I heard someone mention recently in a reply to one of my posts on a Physics book. Bohm’s take on QM was a genuine attempt at doing science that most people recognised as potentially valuable. It's just that the basis for his work, hidden variables, seems to have been disproved. Even so, some still think QM might get some future mileage from Bohm's work.

Much food for though for philosophers of science here in this Bohm's collection of letters ( )