Podcast Summary

Philosophy For Our Times
Episode: In Search of Nothing | David Deutsch, Amanda Gefter, Lee Smolin
Date: November 6, 2025
Host: IAI (Mato Dowd)
Guests: David Deutsch, Amanda Gefter, Lee Smolin

Overview

This episode brings together three prominent voices from physics and philosophy—David Deutsch, Amanda Gefter, and Lee Smolin—to explore the profound question: Is nothing an impossibility? The discussion unpacks the concept of “nothing” from both scientific and philosophical perspectives, probing paradoxes, definitions, and the very nature of existence. The panel addresses whether nothingness can exist, if “something” is inevitable, and whether investigating nothing can yield new insights about our universe.

1. Framing the Debate: What is Nothing?

Start: 01:53

• Host’s Introduction (01:53):
  Sets up nothing as “an absence so absolute that even defining it becomes problematic,” referencing philosophical giants from Hegel to Sartre and raising the paradoxes inherent to the topic.

Opening Responses

• David Deutsch (04:20):

  • Warns against essentialism and dismissing the question as meaningless; instead, real problems arise from the concept of nothing, such as the paradox of time beginning at the Big Bang.
  • Offers the North Pole analogy: asking “what is north of the North Pole?” is a question of terminology, but questions about the structure of the universe (like a torus vs. infinite repetition) are substantive and demand theory.
  • Quote: “Usually a problem is a problem. And unless people are mischievously citing just words, which some philosophers do, then the problem has to be addressed.” (08:05)

• Amanda Gefter (08:23):

  • Recounts her lifelong quest to understand nothingness, sparked by her father’s question at age 15: “How would you define nothing?”
  • Shares a story of John Wheeler’s response: “I like to say the boundary of a boundary is zero,” noting the journey this set her on.
  • Concludes: “What I've come to believe, in a sense, is the opposite of the suggestion…that maybe nothing is the only possibility. And because of that, it's the appearance of something that is inevitable.” (11:00)

• Lee Smolin (11:07):

  • Asserts that none of his developed theories in physics have required a concept of nothing; argues that “nothing exists; things only happen”—the focus should be on change and the rules governing it.
  • Quote: “There’s nothing that we call time which is real, which is really what a plainness would call time. That is, I don’t believe there’s anything that is stationary and unchanging. I think everything changes.” (11:30)

2. Defining “Nothing”

Theme One, 13:40

Philosophical and Physical Approaches

• Deutsch (14:15):

  • Cautions against “what is” questions without theory; supports Smolin’s view that things happen according to rules, but challenges what happens if rules themselves change.
  • Raises a paradox: “Do the rules which change change according to a rule?” (15:27)

• Smolin (15:27):

  • Reflects on progress through paradox, referencing collaborator Roberto Unger: “Bringing oneself into a deep paradox is progress.”
  • Deutsch retorts (15:57): “We want to be able to come out of a deep paradox as well.”

• Gefter (16:18):

  • Argues that “nothing” defined as a negative (no thing, the absence of everything) leads to logical traps; explores her father's proposal to define nothing positively, as “a state of infinite, boundless sameness.”
  • “I think…still to this day I find that like a useful way to think about nothing as kind of this completely invariant, unchanging sameness.” (17:50)

Physics vs. Philosophy: The Vacuum

17:58

• Host: Notes physicists’ “vacuum” isn’t true nothing; it’s an “active” place with laws of nature operating.

• Smolin (18:31):

  • Discusses “vacuum” as the lowest energy state in quantum mechanics; brings up the “metalog dilemma”—how do the laws of physics arise or evolve?
  • “I think that it's real progress to have arrived at that…to understand why the laws of nature would change as we see them do.” (20:10)

• Deutsch (21:19):

  • Quantum field theory makes “nothing” easier philosophically; echoes Gefter’s “sameness” as requiring less explanation than novelty.
  • Argues that the distinction between sameness and novelty is central not just to cosmology but also free will and consciousness.
  • Quote: “This idea that reality is about the distinction between sameness and novelty…comes into all sorts of other philosophical issues.” (22:58)

3. Can We Even Talk About “Nothing”?—The Role of Paradox

Theme Two, 30:11

• Host: Quotes Lewis Carroll and Bertrand Russell—can paradoxes of nothing be “corrected” by fixing our language/logic?

• Smolin (30:58):

  • Russell’s view: many “nothing” problems are linguistic errors—fix the grammar, fix the paradox.
  • “I think that Russell is right about many questions in philosophy turn out to be decidable by improving your language.” (31:14)

• Deutsch (31:59):

  • Cautions: “It’s always dangerous to define away a problem…to just throw away that whole situation and say it’s only a matter of words I think is a mistake.”
  • Invokes Kant’s struggles with the universe’s beginning, resolved only with later mathematics—thus, real problems may hide behind verbal paradoxes.
  • Quote: “We shouldn’t just throw away problems.” (33:20)

• Gefter (36:04):

  • Suggests flipping the question: “What is something?” In physics, reality is often what’s invariant in all reference frames. Notably, progress in physics (from Einstein to holography) keeps revealing supposed invariants to be, after all, observer-dependent.
  • “The progression…seems to open up the possibility that eventually what you're going to find is that the only real thing is nothing.” (37:22)

• Smolin (38:44):

  • Adds even solutions in advanced theories like string theory and general relativity lack true invariants, pushing us further from a classical “something” towards this “nothing.”

4. Observers, Boundaries & Information: John Wheeler’s Legacy

42:26

• Gefter (42:26):

  • Outlines Wheeler’s evolving quest: from particles to spacetime to information as the universe’s foundation.
  • Shares Wheeler’s participatory universe—reality emerges via observers, boundaries (“lines across the empty courtyard”), and relative distinctions; but removing the boundary returns us to nothing.
  • Quote (Wheeler): “There is many a game we cannot play until we draw with chalk a line across the empty courtyard. It doesn't matter where we draw it, but only that we draw it.” (43:00)

• Deutsch (45:57):

  • Critical of Wheeler’s/Bohr’s “information” approach: labels it “supernatural” and “obscurantist,” a means of resisting the many-worlds (Everett) quantum theory.
  • Argues that information is always instantiated on something physical, which itself is not “nothing.”
  • Quote: “Information in the universe is fundamental information, making the universe…That's just all this supernatural stuff.” (47:50)

5. Does Studying Nothing Help Us Understand the Universe?

Theme Three, 50:24

• Smolin (50:24):

  • Shares story of John Wheeler’s excitement over Heidegger; muses on the usefulness of “European philosophy” despite his scientific skepticism.
  • Celebrates the infinite variety in the world and the endless capacity for discovery, paralleling Leibniz: “There’s something enormously celebratory about the idea that the world is infinite in variety, has infinite capacity to teach us and surprise us.” (54:26)

• Gefter (55:23):

  • Echoes “something is nothing, and nothing is something”—references Alan Guth’s observation that all conserved quantities (charge, angular momentum, energy) in the universe sum to zero; thus, “maybe a better way of saying it is that something is nothing.”
  • Quote (Alan Guth): “Maybe a better way of saying it is that something is nothing.” (57:06)
  • Suggests facts within the universe (everything summing to zero) can point back to the fundamental “nothing.”

• Deutsch (58:28):

  • Concludes that seeking absolute bedrock or foundation for all knowledge is mistaken (aligning with Karl Popper); instead, philosophy and science should seek to resolve problems, not foundational truths, enabling endless progress:
  • Quote: “That is the doorway, the open window, to an infinite progress.” (59:40)

6. Notable Quotes & Moments

• David Deutsch:
  “We have to start with the problem and what we're looking for when we're trying to solve a problem is, again, not the final answer. It is an explanation that tells us why the conflicts that we thought that we saw aren't really there...That is a good thing, because that is the doorway, the open window, to an infinite progress.” (58:28–59:53)

• Amanda Gefter:
  “What I've come to believe, in a sense, is the opposite of the suggestion…that maybe nothing is the only possibility. And because of that, it's the appearance of something that is inevitable.” (08:23–11:00)
  “If you could take the sort of God's eye view from outside of reality, I think then what you would see is that sameness. You would see the nothing. But by definition, you can't be outside of that…” (26:08)
  “Maybe a better way of saying it is that something is nothing.” — Alan Guth, via Gefter (57:06)

• Lee Smolin:
  “All that exists, first of all, nothing exists. Things only happen, and things that happen happen according to some rules which are developed in time and change in time.” (11:07–11:30)
  “Bringing oneself into a deep paradox is progress.” (15:27)

• John Wheeler (via Gefter):
  “The boundary of a boundary is zero.” (08:23)
  “There is many a game we cannot play until we draw with chalk a line across the empty courtyard. It doesn't matter where we draw it, but only that we draw it.” (43:00)

7. Key Timestamps

• 04:20 - Deutsch on the Big Bang and the North Pole analogy
• 08:23 - Gefter’s journey and Wheeler anecdote
• 11:07 - Smolin on events vs. existence
• 16:18 - Gefter attempts positive definition of nothing
• 17:58 - Physics vacuum vs. philosophical nothing
• 21:19 - Deutsch on the necessity of novelty and sameness
• 26:08 - Gefter on observer-dependent vacuum states
• 31:59 - Deutsch on not defining away problems
• 36:04 - Gefter: “something” as observer-invariant
• 42:26 - Wheeler’s chalk line and participatory universe
• 55:23 - Gefter on conserved quantities summing to zero
• 58:28–59:53 - Deutsch’s closing remarks on infinite progress

Conclusion

The episode unearths the central paradox of “nothing”—seen not as a philosophical dead-end, but as a driver for inquiry in both physics and philosophy. Whether defined through invariance, observer-dependence, or the balance of conserved quantities, “nothing” remains a fertile and elusive concept. The panel converge on the notion that genuine progress comes from tackling paradoxes head-on and embracing the infinite complexity of the universe, rather than settling for final answers.