Epicurus' Prolepsis vs Heraclitus' Flux

Rolf I am obviously not an expert on this either, nor have I found time to read the books I am about to recommend, but consistently over the years i have had people tell me that a very good resource is Victor Stenger:

Victor Stenger

I may come back and delete this post later if i find better information, but I think we have an obligation to those who "lurk" but don't participate not to let a debate go too far in a certain direction without refocusing it on making sure it is consistent with the purpose of the forum.

Pending further research I have posed the following question to the latest Grok and I believe the response, especially in its opening restatement of the question, is helpful with a general understanding of the issues involved. Even if details of the positions attributed to the particular individuals prove to be incorrect, this still seems to me to be a helpful summary.

Those who have time and inclination can parse through this response and continue to discuss it's accuracy or inaccuracy. Those who do not have time or inclination to do so will still gain, in my view, an appreciation that there are complex issues here, many of which are not "settled."

I hope those who are interested in this will continue to hammer out these issues.

Question:  

What modern physicists, if any, continue to maintain a "physicalist" model of the universe as opposed to those models which are more consistent with a Herclitean flux where certain knowledge is impossible?

Answer:

The distinction between a "physicalist" model of the universe and a Heraclitean flux perspective, where constant change undermines certain knowledge, is a deep philosophical divide in modern physics.

Physicalism, in this context, refers to the view that the universe is fundamentally composed of physical entities governed by consistent, discoverable laws, often tied to a mechanistic or reductionist framework. A Heraclitean flux perspective, by contrast, emphasizes constant change, indeterminacy, and the limits of certain knowledge, aligning with interpretations that prioritize process, emergence, or fundamental uncertainty (e.g., some interpretations of quantum mechanics).Below, I’ll outline key modern physicists and their leanings, based on their work and public statements, focusing on whether they align with a physicalist model or a Heraclitean flux-like view. Since direct evidence of their philosophical stances is often implicit, I’ll draw from their contributions, writings, and interviews, supplemented by web and X post analysis where relevant. Note that many physicists don’t explicitly label themselves as physicalists or flux advocates, so I’m inferring based on their approaches to fundamental physics.

Physicists Aligned with a Physicalist Model: Physicalist-leaning physicists tend to favor theories that seek unified, objective, and deterministic (or at least predictable) descriptions of reality, often rooted in reductionism or the belief that fundamental laws govern all phenomena.

1. Sean Carroll
   • Position: Theoretical physicist, known for work in cosmology, quantum mechanics, and the foundations of physics.
   • Physicalist Leanings: Carroll is a prominent advocate of the "core theory" (quantum field theory plus general relativity) as a complete description of everyday phenomena. He supports a physicalist worldview through his promotion of naturalism and the idea that the universe is governed by fundamental laws, as seen in his book The Big Picture (2016). His Everettian (many-worlds) interpretation of quantum mechanics assumes a universal wavefunction, which, while non-deterministic in observation, is deterministic in its evolution, aligning with physicalism.
   • Evidence: In his blog posts and podcasts (e.g., Mindscape), Carroll emphasizes that physics provides a reliable framework for understanding reality, rejecting metaphysical uncertainties that undermine objective knowledge.
   • Counterpoint: His acceptance of emergent phenomena (e.g., consciousness) might resonate with flux-like ideas, but his commitment to underlying laws keeps him firmly physicalist.
2. Steven Weinberg (deceased 2021, but influential in modern physics)
   • Position: Nobel laureate, known for contributions to the electroweak theory and cosmology.
   • Physicalist Leanings: Weinberg was a staunch reductionist, arguing in Dreams of a Final Theory (1992) that physics could, in principle, uncover a unified theory of everything. He viewed the universe as governed by simple, universal laws, a hallmark of physicalism.
   • Evidence: His writings dismiss speculative or flux-like views that prioritize indeterminacy, focusing instead on the predictive power of physical theories.
   • Counterpoint: Weinberg acknowledged the limits of current knowledge (e.g., in quantum gravity), but his goal was always a complete, objective description, not a Heraclitean flux.
3. Lisa Randall
   • Position: Theoretical physicist, known for work on extra dimensions and particle physics.
   • Physicalist Leanings: Randall’s work on models like the Randall-Sundrum framework assumes a universe with consistent, discoverable physical structures (e.g., extra-dimensional branes). Her books, like Knocking on Heaven’s Door (2011), emphasize the power of the scientific method to uncover objective truths.
   • Evidence: Her focus on testable predictions and mathematical rigor aligns with a physicalist commitment to stable, knowable laws.
   • Counterpoint: She acknowledges complexity in cosmology, but her approach remains reductionist, not flux-oriented.
4. Brian Greene
   • Position: String theorist and popularizer of science.
   • Physicalist Leanings: Greene’s work on string theory seeks a unified framework for all physical interactions, assuming a fundamental, law-governed reality. In The Elegant Universe (1999) and The Fabric of the Cosmos (2004), he presents the universe as ultimately comprehensible through physical laws, even if those laws involve high-dimensional strings.
   • Evidence: His advocacy for string theory and his rejection of overly speculative, non-testable ideas suggest a physicalist stance.
   • Counterpoint: String theory’s untestable nature could align with flux-like uncertainty, but Greene’s optimism about eventual empirical confirmation keeps him in the physicalist camp.

Physicists Aligned with a Heraclitean Flux Perspective: Physicists leaning toward a Heraclitean flux view often embrace indeterminacy, emergent phenomena, or the idea that reality is fundamentally process-based or unknowable in an absolute sense. This aligns with interpretations of quantum mechanics (e.g., Copenhagen or QBism) or theories emphasizing complexity and change.

1. Lee Smolin
   • Position: Theoretical physicist, known for loop quantum gravity and cosmological natural selection.
   • Flux Leanings: Smolin explicitly critiques reductionist physicalism in books like Time Reborn (2013), arguing that time is fundamental and the universe evolves through dynamic processes, not fixed laws. His cosmological natural selection hypothesis suggests laws themselves may change, resonating with Heraclitean flux.
   • Evidence: Smolin’s rejection of timeless, universal laws and his emphasis on relational, evolving systems (e.g., in loop quantum gravity) align with a flux-like view where certain knowledge is limited by the universe’s inherent changeability.
   • Counterpoint: He still seeks mathematical frameworks, which could be seen as physicalist, but his focus on process over static laws leans toward flux.
2. Carlo Rovelli
   • Position: Theoretical physicist, co-founder of loop quantum gravity.
   • Flux Leanings: Rovelli’s relational interpretation of quantum mechanics and his book The Order of Time (2017) emphasize that reality is fundamentally relational and time-dependent, with no fixed, objective structure. He argues that physics reveals a world of processes, not things, aligning closely with Heraclitean flux.
   • Evidence: His writings, such as Helgoland (2020), embrace quantum indeterminacy and the limits of absolute knowledge, suggesting that our descriptions of reality are always contextual.
   • Counterpoint: Rovelli’s commitment to mathematical rigor might seem physicalist, but his philosophical stance prioritizes change and relationality.
3. Nima Arkani-Hamed
   • Position: Theoretical physicist, known for work on the amplituhedron and fundamental physics.
   • Flux Leanings: While Arkani-Hamed works on unifying theories, his exploration of the amplituhedron suggests that space and time may not be fundamental, but emergent from more abstract structures. This challenges physicalist assumptions of a fixed spacetime framework and aligns with a flux-like view where reality is process-based.
   • Evidence: His lectures (e.g., at the Institute for Advanced Study) emphasize that traditional notions of particles and fields may be illusions, pointing to a deeper, dynamic reality.
   • Counterpoint: His search for new mathematical frameworks could be seen as physicalist, but the radical rethinking of spacetime leans toward flux.
4. David Bohm (deceased 1992, but influential)
   • Position: Quantum physicist, known for the Bohmian interpretation of quantum mechanics.
   • Flux Leanings: Bohm’s concept of the “implicate order” in Wholeness and the Implicate Order (1980) describes reality as a dynamic, interconnected process, where the universe unfolds and enfolds in a constant flux. This rejects the static, particle-based physicalism of classical physics.
   • Evidence: His emphasis on holism and the impossibility of fully separating observer from observed aligns with Heraclitean ideas of constant change and epistemic limits.
   • Counterpoint: Bohmian mechanics is deterministic, which could seem physicalist, but its holistic, process-based ontology is flux-like.

Mixed or Ambiguous Positions: Some physicists straddle the line, acknowledging both the power of physical laws and the limits of certain knowledge:

1. Roger Penrose
   • Position: Mathematical physicist, known for work on black holes and consciousness.
   • Mixed Stance: Penrose’s work on general relativity and quantum gravity (e.g., twistor theory) seeks objective laws, aligning with physicalism. However, his ideas about the limits of computation (e.g., in The Emperor’s New Mind, 1989) and the cyclic cosmology model suggest a universe with fundamental uncertainties and dynamic cycles, leaning toward flux.
   • Evidence: His recent work on conformal cyclic cosmology emphasizes change and renewal, but he remains committed to mathematical objectivity.
   • Conclusion: Penrose blends physicalist rigor with flux-like openness to radical change.
2. Sabine Hossenfelder
   • Position: Theoretical physicist, known for critiques of modern physics.
   • Mixed Stance: Hossenfelder is a physicalist in her commitment to testable state laws, as seen in her book Lost in Math (2018).
   • Evidence: Her critiques of speculative theories (e.g., multiverse) show skepticism of flux-like indeterminacy, but her acknowledgment of quantum randomness and the limits of current theories introduces a flux-like humility.
   • Conclusion: She leans physicalist but is open to the limits of knowledge.

Summary

• Physicalist-Leaning Physicists: Sean Carroll, Steven Weinberg, Lisa Randall, Brian Greene. These physicists emphasize stable, discoverable laws and a reductionist view of the universe.
• Flux-Leaning Physicists: Lee Smolin, Carlo Rovelli, Nima Arkani-Hamed, David Bohm. These thinkers embrace dynamic, relational, or emergent views where change and uncertainty limit absolute knowledge.
• Mixed Cases: Roger Penrose, Sabine Hossenfelder, who balance objective laws with openness to fundamental change or limits.

The divide reflects ongoing debates in physics about whether the universe is a fixed, knowable system or a dynamic, ever-changing process.

Quote from Martin

Grok misclassified Sabine Hossenfelder. Her insistence on hard determinism makes her the most extreme physicalist among those listed.

I suspect you are correct but can neither confirm nor deny. However I think the way you phrased that is very helpful for leading to the question: Does hard determinism presuppose physicalism? I suspect that at least some hard determinists would disagree with that, but I see that as one of those intersection questions between philosophy and physics.

In partial answer to Rolf and DaveT, my exhibit A on this issue, and I am sure there are many more when I go looking, is Lawrence Krauss and his "A Universe From Nothing," which I have referenced before as the subject of a video debate between Krauss and Richard Dawkins:

Quote from From Amazon Listing

A Universe from Nothing: Why There Is Something Rather than Nothing Paperback – January 1, 2013

by Lawrence M. Krauss (Author), Richard Dawkins (Afterword)

https://m.media-amazon.com/images/I/81nt1V1DDcL._SY466_.jpg

Bestselling author and acclaimed physicist Lawrence Krauss offers a paradigm-shifting view of how everything that exists came to be in the first place.

“Where did the universe come from? What was there before it? What will the future bring? And finally, why is there something rather than nothing?”

One of the few prominent scientists today to have crossed the chasm between science and popular culture, Krauss describes the staggeringly beautiful experimental observations and mind-bending new theories that demonstrate not only can something arise from nothing, something will always arise from nothing. With a new preface about the significance of the discovery of the Higgs particle, A Universe from Nothing uses Krauss’s characteristic wry humor and wonderfully clear explanations to take us back to the beginning of the beginning, presenting the most recent evidence for how our universe evolved—and the implications for how it’s going to end.

(underlining added)

If this forum were dedicated only to the discussion among existing members, all of whom were well grounded in physics, the issue I am about to discuss would not be necessary to confront. But I don't think that "experts" were the main target of Epicurus, nor do I want this forum to require all discussion of physics to conform to the latest speculations of string theory or whatever is the fashion of the day.

Regular people need a coherent explanation of the nature of the universe that they can internalize and feel confident that the basics of a natural explanation are solid. We need not be able to reconstruct the universe ourselves just because atomism makes more sense than any other physics theory, we simply need one of more understandable frameworks of analysis that satisfies us that supernatural explanations are not required.

My reasoning behind the position I take is that ever since I took physics in college, and every year since then, I have been confronted with laymen arguments such as "Heisenberg's uncertainty principle" and "Schrödinger's cat" mean that the universe is ENTIRELY unpredictable, with the stated or unstated premise that as a result the preferred posture for an intelligent person is either total skepticism or return to supernaturalism.

I point to Lawrence Krauss' sensationalist book title, along with Richard Dawkins' perceived need to object on much the same grounds i am stating here, as just one of the recent examples of the same issue. My reading of Krauss' book is that he is fudging on what "nothing" really means, but he has structured his title and argument, as exemplified in the Youtube blurb, in a way that I perceive as entirely calculated to disrupt any confidence anyone might have in anything. Unless - that is - they hand themselves over to the physicist experts who allegedly have some esoteric knowledge that is unavailable to normal people, and in fact has in the past always been unavailable to anyone, from Leonardo da Vinci on down, without modern technological discoveries. The further implication is that we should consider ourselves fortunate we are to have such people as Krauss now to lift us to a new golden age, if we will only ask them how to live!

That attitude is bunk, but I think that's exactly what Epicurus was confronting in terms of the size of the sun arguments and the other assertions of the mathematicians and logicians of his own day.

The objections raised by Martin and Tau Phi are representative of good faith objections we have seen before and will see many times again.

I perceive Martin's concerns to be the standards of writing here at the forum -- that we not countenance the equivalent of flat earth theories that fly in the face of all evidence. I think most everyone here would agree with that, including me, but the kind of issues involved in the arguments of Krauss and others, which do in fact arrive back at Heraclitean indeterminacy, and which other highly-educated people are rebutting, are not in that category.

I perceive Tau Phi's concerns, which were also stated in our Zoom last night with more specificity, as being consistent with his more skeptical attitude that he freely states. The skeptical argument since before the time of Cicero to today is that is simply not necessary to take sides at all on any aspects of physics. I am sure he has a different take on his own position, but I would analogize his position to the position Frances Wright takes in "A Few Days In Athens" - she hardly mentions physics or necessity at all in her book, and to the extent she does mention it her statements are largely at odds with Epicurus' own. Her position in my reading amounts to the view that we should concern ourselves purely with ethics and not concern ourselves with infinity, eternality, or most anything outside the confines of the earth. In the end, Frances Wright's book, as brilliant as it is, did not lead to anything further for Epicurean philosophy, or for her personally (as far as I can tell), and that's what I perceive to be the reason why. Radical skepticism is ultimately totally unsatisfying, self-refuting, and leads nowhere.

I respect both Martin's and Tau Phi's viewpoints, they are friends of mine, and they bring much that is helpful to the forum. But Epicurus felt that it IS necessary to develop theories that oppose those of the radical skeptics and hard determinists and logicians -- even more than one theory if necessary -- and that IS necessary to be willing to draw conclusions on issues of ultimate concern to us. Is there life after death? Are there supernatural forces? Those questions cannot be EMPIRICALLY answered because we have not ourselves lived forever or observed everything in the universe, and anyone who proposes such a standard of certainty is on a fool's errand and asserting a standard that is both nonsensical and not something that they apply to other necessary day to day decisionmaking.

The question of "When is the evidence enough?" to justify reaching a conclusion is not one a physicist can answer -- not now, and not in another thousand years. And it makes no sense whatsover to conclude "we'll never know" so maybe we should hedge our bets and act as if there are supernatural forces and maybe our consciousness will survive death. There is plenty of evidence that contradicts those positions, and it is radical skepticism that both nonsensical, self-contradictory, and perverse to require us to apply that kind of standard of "certainty" to the most important questions of life.

Whether the ultimate particles are "hard" or "soft" or exactly why they "bounce" or exactly how they move are issues which will almost certainly not be determined in our lifetimes or ever. But what we already have, however, is reams of evidence that something like that DOES happen, and does support a general theory of ultimate particles. What we already have is amply sufficient to form a basis for explaining that the universe is natural in the face of those who insist that it is supernatural.

Coming to a close here, I believe Epicurus' point is that is the role of a practical philosophy to provide a framework for successful living. A large part of that framework requires a working theory that the universe is natural and operates regularly according to predictable principles. It cannot be accepted that a proper understanding of life requires a lifetime of dedication to abstract physics, nor can it be accepted that those who do devote their lives to such a pursuit are entitled to deference in every important conclusion of life - conclusions on which they themselves are divided and often attached to views that defy natural and ordinary experience.

That's why it makes sense to me to stay the course with Epicurus' strategy. Not every precise detail, but to his clearly-stated strategy of deducing reasonable conclusions based on available evidence.

To the extent possible we can and should explore the latest developments in physics and astronomy and everything else, and make sure that the latest discoveries ultimately can be reconciled with a natural order of things. But there is absolutely no reason to expect that this basically naturalistic viewpoint is going to be overturned tomorrow or in ten million years by viewpoints such as "everything flows" and therefore "nothing is unknowable." Those views were self-contradictory and absurd from the first moment they were asserted thousands of years ago, and they remain today and will remain forever self-contradictory and absurd.

We cannot be afraid not to be assertive on these points, even if we ourselves have not devoted our lives to the latest speculations in physics.