Zoom of 29-03-22

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Sunday March 29, 2026 - Zoom Discussion 12:30 PM EST - Lucretius Book Review - This Week: A Quick Look At Sedley’s “Epicurean Anti-Reductionism”

1. Welcome and news / requests for new topics. We’ll continue to deal with individual topics as they occur. Just message me and we will set up an agenda each week that allows for new topics.
2. Every session let’s try to cover questions like:
   1. What is the context of this section?
   2. Why included at this point in the presentation?
   3. What are the major points Lucretius is making?
   4. What are the implications of these points?
3. Notes on New Topics / Announcements:

• This week I would like us to take a step back from where we are in Lucretius so that David Sedley can explain the implications of the detail through which we are going about atoms and void.

• As a jumping off point I want to quote Joshua from this past week’s podcast at about the 28:43 mark:

  • In the first book of On Ends, Cicero is in conversation with Torquatus and makes a number of the same points that we’ve been talking about here. He points out that Epicurus derives his atomism from Democritus, but complains that he makes very few modifications to it, saying that Democritus believes in certain things, which he terms atoms, that his bodies are so solid as to be indivisible, moving about in a vacuum of infinite extent, which has neither top, bottom nor middle, neither center nor circumference. The motion of these atoms is such that they collide and cohere together, and from this process result the whole of the things that exist and that we see. Moreover, this movement of the atoms must not be conceived as starting from a beginning, but as having gone on from all eternity. And Cicero says there is a great deal in both Epicurus and Democrat with which I disagree, he says, but especially in the study of nature, there are two questions to be asked.

• We’ve talked previously about his article “Epicurus’ Refutation of Determinism” which discusses these issues, but the same questions are explored with greater detail and clarity in this article:

  Thread

  Article - David Sedley - 1988 - “Epicurean Anti-Reductionism”

  We’ve referenced many times on the forum the comments about this topic made by David Sedley in his “Epicurus’ Refutation of Determinism.”

  I don’t think we previously cited - or that I knew of - an article Dr. Sedley had written directly on point:

  Epicurean Anti-Reductionism - 1988 - J. Barnes, M. Mignucci (eds.), Matter and Metaphysics (Naples 1988), 295-327

  Full article available here:

  https://www.academia.edu/3051123/Epicurean_anti_reductionism

  Summary of Main Arguments and Highlights

  1. Core Thesis: Epicureanism is Not Fully Reductionist

  • Sedley’s central claim is that Epicurean philosophy, although grounded in atomism, cannot be understood as a purely reductionist system.

    • While everything is composed of atoms and void, Epicurus does not reduce all explanations to atomic properties alone.
    • Instead, Epicureanism allows for higher-level explanations that are not eliminable into micro-level physics.

    Key implication:
    Epicurus is a qualified materialist, not a strict reductionist.

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  2. Distinction Between Atoms and Compounds

  • Sedley emphasizes a crucial distinction:

    • Atoms: possess only a few immutable properties (shape, size, weight).
    • Compound bodies: exhibit qualities that do not belong to atoms themselves.

    This aligns with Lucretius’ distinction between:

    • Coniuncta (necessary qualities)
    • Eventa (accidental qualities)

    These qualities:

    • Depend on atomic arrangements
    • But are not reducible to atomic descriptions

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  3. Emergent Qualities Are Real (Not Illusions)

  • A central anti-reductionist point:

    • Qualities like color, heat, solidity, life, and agency are:
      • Not properties of individual atoms
      • Yet genuinely real features of compound bodies

    Sedley stresses that Epicurus:

    • Does not treat these as mere appearances or illusions
    • Instead treats them as objective, though derivative, realities

    Conclusion:
    Epicureanism supports a form of emergence—higher-level properties arise from but are not identical to lower-level constituents.

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  4. Explanatory Pluralism

  • Sedley argues that Epicurus uses multiple levels of explanation simultaneously:

    • Micro-level: atoms and their motions
    • Macro-level: observable phenomena and qualities

    These levels are:

    • Compatible, but
    • Not interchangeable

    Thus:

    • Some explanations are best given at the level of bodies, not atoms.

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  5. Rejection of Eliminative Reductionism

  • Epicurus rejects the idea that:

    Quote

    Quote

    Only atomic-level facts are “really real”

    Instead:

    • Observable properties retain explanatory legitimacy
    • Everyday descriptions (e.g., “fire is hot”) are philosophically valid

    This is a direct rejection of:

    • The view that higher-level properties must be eliminated in favor of physics

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  6. Stability and Identity of Objects

  • Sedley highlights that:

    • Compound bodies have stable identities
    • These identities depend on:
      • Structural organization
      • Functional roles

    Not merely:

    • A list of atomic constituents

    Thus:

    • A thing’s identity is tied to its emergent organization, not just its atoms

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  7. Ethical and Psychological Implications

  • This anti-reductionism is not merely physical—it extends into ethics:

    • Human experiences (pleasure, pain, fear) are:
      • Grounded in atomic processes
      • But must be understood at the level of lived experience

    Epicurus therefore:

    • Treats psychological states as real and explanatorily significant
    • Not reducible away into physics

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  8. Lucretius as Key Evidence

  • Sedley relies heavily on On the Nature of Things to support this interpretation:

    • Lucretius explicitly distinguishes:
      • Atomic properties
      • Emergent qualities of bodies
    • He shows that:
      • Qualities arise from arrangements and interactions, not intrinsic atomic features

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  Overall Interpretation

  • Sedley’s interpretation can be summarized as follows:

    • Epicurus is a materialist → everything is made of atoms and void
    • But also an anti-reductionist → not everything can be explained purely at the atomic level

    This results in a philosophical position that combines:

    • Ontological reduction (everything is atoms)
    • With explanatory pluralism (not everything is explained in atomic terms)

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  Concise Takeaway

  • Quote

    Quote

    Epicurean philosophy holds that while atoms are the fundamental constituents of reality, the world we experience—including qualities, objects, and human life—must be understood at their own level and cannot be reduced away into atomic descriptions.

Discussion / Problems of Reductionism

• Bricks and houses
• Colors - What is real is broader for Epicurus than Democritus
• Downward Causation - https://philosophyofbrains.com/2007/04/05/examples-of-downward-causation.aspx
• What are the concerns that arise from Reductionism?
  • Does atomism really explain life without need for an overlay of supernatural organization?
  • Problems of “reality” - is our level truly “real” or are we living an illusion?
  • Does reductionism lead to determinism?
  • Can life ultimately be explained TOTALLY in terms of its constituent atoms?
  • What does “emergent properties” really mean?
  • If no outside forces, what is the explanation of the swerve?