Podcast Summary

New Books Network: Physics Fixes All the Facts by Liam Graham

Host: Gregory McNiff
Guest: Liam Graham
Release Date: November 5, 2025

Episode Overview

This episode features a deep-dive interview with Liam Graham about his book, Physics Fixes All the Facts (Springer Nature, 2025). Drawing from his background in physics, philosophy, and economics, Graham explores one of the most fundamental questions: "Is physics enough to describe reality, or is something more required?" The discussion addresses emergence, reductionism, the philosophy of science, and the boundaries between physics and other domains—from hurricanes to consciousness—using both accessible examples and rigorous reasoning.

Key Discussion Points and Insights

Why Write the Book? Who Is it For?

[04:06]

• Graham was motivated by the question of whether physics suffices to explain all phenomena, particularly those labelled as "emergent."

• "Is emergence about something beyond physics? I really needed to get grips with that question for my personal satisfaction, and the result ... turned into this book." – Liam Graham

• The book targets readers interested in the fundamental nature of reality, with caveats: it assumes some familiarity with physics and philosophy of science.

The Causal Exclusion Argument (Jae Wong Kim)

[05:21]

• Kim's philosophical argument: Either causation is at the level of fundamental physics (atoms, particles), or at a higher, emergent level (e.g., meteorological systems for hurricanes).
• "Now, nothing can have two causes ... So these are the only two possibilities. Either it's physics or it's a higher level. The higher level is generally called emergence." – Liam Graham

Six Positions on Emergence

[08:03]

• Graham, following Jessica Wilson's philosophical framework, explains six positions—primarily:

  • Dualism: Non-physical causation (e.g., "spirit of the winds")
  • Strong Emergence: Higher-level physical causes that still violate current physics
  • Weak Emergence: Higher-level phenomena that don't contradict physics

• "With both dualism and strong emergence ... they must violate the laws of physics. If they don't, physics is what's running the show." – Liam Graham

Levels of Description: Real or Constructed?

[10:19]

• Emergence often presupposes the existence of "levels," but Graham argues these are mental constructs—chosen for convenience, not fundamental divisions in reality.
• "These different levels don't exist in reality. They're just approximations that we choose ... These explanations are in our heads. They're not in the world." – Liam Graham [12:38]

Fundamental Physics: Limits and Approximations

[13:26]

• Even "fundamental" physical theories are provisional—quantum field theory could be outdated tomorrow. Any attempt at fundamental description is itself contingent.
• "Even if there are no open questions in physics, we never know whether just outside the range of our experiments is lurking something we don't understand." – Liam Graham [13:26]

Weak vs. Strong Emergence

[14:53], [18:59]

• Weak Emergence: Often summarized as "more is different"; but Graham argues "more is always physics" since physical interactions always create new behaviors with added complexity—no mystical emergence here.

  • "Describing systems as weakly emergent adds nothing." – Liam Graham [16:43]

• Strong Emergence: Suggests higher-level causes with discontinuous effects, not reducible to underlying physics.

  • “If we found a phenomena which would be classed as strongly emergent ... it would turn out to be either new physics or dualism. And this is really the conclusion that my book draws about the nature of reality. It’s either physics or dualism. There’s no middle ground.” – Liam Graham [18:59–21:40]

Thought, Brains, and Consciousness

[17:11], [25:31], [27:53], [28:15], [30:40]

• Graham equates the complexity of the brain to that of a hurricane: both are just complex arrangements of molecules governed by physics.
  • "I don't see any philosophical difference ... they're two complex physical systems." – Liam Graham [17:11]
• On consciousness: It’s likely a "weird side effect" of brain structure—fascinating, but currently outside the realm of scientific evidence.
  • “The study of it is a complete and utter mess ... There’s not a shred of objective evidence. We’re all convinced we have it, but there’s no objective evidence.” – Liam Graham [28:15]

Austere Physicalism / Eliminativism

[25:31]

• Austere physicalism (or eliminativism): All higher-level concepts (beliefs, desires, psychological terms, even "emergence") will eventually be eliminated in favor of descriptions at the most fundamental physical level.

  • "All our familiar concepts ... are just approximations, are just illusions. And this is why it's austere, because all that is real in this world is fundamental physics, or our best guess at fundamental physics." – Liam Graham

• Physicalism vs. Materialism: Just a change in terminology; physics today describes far more than "material" (e.g., fields, energy) [29:51].

  • “It became evident that physics is about much more than matter ... there's no real change in the meaning.” – Liam Graham

Kant, Perception, and Reality

[30:49]

• We perceive only vague, incomplete shadows of reality; the “thing-in-itself” (noumenon) is forever out of reach.

  • "We're trapped in our senses and we just see some vague shadow of what is probably a insanely complex high dimensional world..." – Liam Graham

• Our scientific approximations to reality improve, but may always be far from "what is actually out there." [31:47]

The Map Is Not The Territory

[32:53]

• Many “emergent” mathematical models in physics assume infinities (e.g., phase transitions in the Ising model). But every real, finite, physical system is continuous, never truly discontinuous.
  • "There are no infinite systems in nature ... you can prove for the Ising model and in general that all finite systems are continuous." – Liam Graham

Emergence As A Useful Crutch

[36:17]

• Emergence is a conceptual tool—useful as a "crutch" for thinking about complex systems, often signifying interesting, not yet understood physics.
  • "When you see the term emergence, it often means that we just don’t properly understand the underlying physics.” – Liam Graham

Language and Causation

[38:00]

• Graham doesn't mind people using "emergence" in vernacular, but stresses: all causation arises from basic physical interactions.

  • "All this term emergence means is arising from interactions ... the causation happens at the level of physics, which describes both the particles and their interactions and hence everything in the universe." – Liam Graham

The Meaning of Life (Entropy and Bleak Honesty)

[38:58]

• From a physicalist standpoint, complex systems—including life and intelligence—exist to speed up the universe’s march toward maximum entropy (disorder).
  • “If you take austere physicalism seriously, there is no escape. We are just physical systems like any other. We're like the hurricane, just a bit fancier.” – Liam Graham [38:58]
  • “We by existing are hastening the universe to its end.” – Liam Graham [40:40]

What Would Convince Graham of Emergent Properties?

[41:54]

• "Take a finite physical system ... and show it's discontinuous. Explain how your emergent property ... springs into existence when it gets to a certain size—that will be strongly emergent." – Liam Graham

Heuristics and Human Thinking

[42:53]

• Evolution has given us "fast and frugal heuristics" (rules of thumb) for practical thinking because exact physical computations are infeasible for organisms.
  • Example: Catching a ball is done by keeping the angle constant, not calculating a trajectory.
  • “Fast and frugal heuristics are the ones that evolution gave us.” – Liam Graham

Renormalization Group and Models

[45:21]

• The renormalization group is a powerful mathematical tool in theoretical physics, but relies on models with infinite systems; it describes our models, not the universe directly.
  • "There's no renormalization group in reality, it's a model with assumptions of infinity." – Liam Graham

Notable Quotes & Memorable Moments

• On all of science being approximation:
  "Everything is an approximation to reality because we just can't deal with the infinite complexity of the world." – Liam Graham [12:38]

• On the challenge of defining consciousness:
  "Last year, a paper was published which listed 350 definitions of consciousness." – Liam Graham [28:15]

• On our perceptions:
  "We’re trapped in our senses and we just see some vague shadow of what is probably a insanely complex high dimensional world..." – Liam Graham [30:49]

• On physicalism vs. emergence:
  "All this term emergence means is arising from interactions. There's no contradiction between physics and emergence." – Liam Graham [38:00]

• On the meaning of life:
  "If you take austere physicalism seriously, there is no escape. We are just physical systems like any other. We're like the hurricane, just a bit fancier." – Liam Graham [38:58]

• On what would convince him of emergent properties:
  "Take a finite physical system of your choice ... and show it's discontinuous ... that will be strongly emergent." – Liam Graham [41:54]

Important Timestamps

• [04:06] Graham's motivation and target audience for the book
• [05:21] Kim's Causal Exclusion Argument and its implications
• [08:03] Six philosophical positions on emergence explained
• [10:19] "Levels" as constructs vs. real features of nature
• [14:53] Definitions of weak and strong emergence
• [17:11] The physicalist view on mind and brain
• [25:31] Austere physicalism and eliminativism defined
• [28:15] The mess of consciousness studies
• [30:49] Kant, perception, and the unknowability of the "noumenon"
• [32:53] Why phase transitions and discontinuities are artifacts of infinite idealizations
• [38:58] The "meaning of life" as maximizing entropy
• [41:54] Empirical criteria for strong emergence
• [42:53] Evolutionary heuristics and the limits of reason
• [45:21] The renormalization group: model or reality?

Tone and Overall Feel

Graham is methodical, rigorous, but refreshingly honest—his “brutal consistency” is continually noted and praised by the host. The tone is accessible but unapologetically demanding, as Graham refuses to sugarcoat difficult topics like reductionism or the bleak implications of austere physicalism. The conversation is dynamic and wide-ranging, with the host persistently pushing for clarity and practical summaries.

Summary

This episode provides an incisive and uncompromising exploration of scientific realism and the philosophy of emergence. Graham’s view is clear: for all the apparent complexity and hierarchy in the universe, when it comes to causation and “what’s real,” it’s physics all the way down—or else, it’s dualism, magic, or illusion. Emergence, in his view, is a convenient crutch for our limited minds but offers no mystery unaccounted for by physical interactions. It’s a challenging, thought-provoking, and intellectually honest conversation for anyone seeking to understand the foundational debates at the intersection of physics, philosophy, and the mysteries of the mind.