Podcast Summary: Brain Science with Ginger Campbell, MD

Episode BS 213: Kevin Mitchell Explores Free Will

Release Date: October 27, 2023
Host: Dr. Ginger Campbell
Guest: Dr. Kevin Mitchell (Neuroscientist, Author of "Free Agents: How Evolution Gave Us Free Will")

Main Theme & Purpose

This episode features an in-depth conversation between Dr. Ginger Campbell and neuroscientist Kevin Mitchell about the nature of free will, its relationship to neuroscience, evolution, and agency. Mitchell's new book, "Free Agents: How Evolution Gave Us Free Will," challenges the popular scientific and philosophical view that free will is an illusion, arguing instead that agency and choice are core outcomes of biological evolution. The discussion bridges neuroscience, philosophy, evolutionary biology, and physics to provide an accessible yet rigorous account of how free will can emerge naturally—and why it matters.

Key Discussion Points & Insights

1. Dr. Kevin Mitchell’s Background & Approach (04:18–09:35)

• Mitchell is a developmental neurobiologist and geneticist, focused on brain wiring and individuality.
• His previous book "Innate" explored how our brains are shaped by genetics and development, not solely experience.
• Motivated by common questions about how innate predispositions relate to free will, Mitchell set out to connect philosophical debates about agency with modern neuroscience research.
  • “So really what I wanted to do in this new book, Free Agents, was... try and tackle free will, and ask the question, does neuroscience, does behavioral genetics, does any of these other sciences really threaten or undermine our sort of common conception of being somewhat, at least in control of our own actions?” [07:06, Mitchell]

2. Clarifying Predisposition vs. Determinism (08:28–10:04)

• Genes and brain development provide predispositions, not strict determinants.
• There is room for “things to be genuinely up to us.”
  • “Our behaviors influenced, but not driven in that reductive way by our genes or indeed by our neurons.” [09:21, Mitchell]

3. Evolution, Agency, and the Origins of Purpose (10:04–22:20)

• Common debates about free will get tangled with moral philosophy; Mitchell instead grounds agency in biology.
• Explores the concept that all living things, from bacteria upwards, display goal-directedness and agency.
• The cell membrane marks a key evolutionary step, creating a causally insulated “self” capable of acting in pursuit of persistence.
  • “What really is the essential difference between life and nonlife? ... activity. Living things are hives ... of activity, right? And they're trying to keep themselves alive. That's what being a living thing entails...” [13:54, Mitchell]
• The emergence of basic sensory systems and even simple behaviors (e.g., movement towards food) establish meaning, value, and purpose in a natural, non-mystical sense.

4. Are Simple Organisms Agents? (22:20–26:18)

• Even single-celled organisms can integrate multiple signals and make proactive choices.
• Agency is defined by the whole organism making integrative decisions for reasons relevant to survival—not simply by component mechanisms.
  • “It's an agent, or at least a proto agent... a proactive organism. It's not just sitting there waiting... it's proactive.” [24:50, Mitchell]

5. How vs. Why Explanations in Biology (26:18–29:27)

• Biology is historical and purpose-driven; why-questions (focused on adaptation and persistence) are as scientifically valid as “how” explanations.
• Reductionist, momentary mechanistic views miss the rich, historical context of living agency.

6. Refuting Mechanistic Arguments Against Free Will (31:49–35:45)

• Mitchell addresses three levels of skepticism:
  • Biological fatalism: “I'm just acting out my programming.”
  • Neural reductionism: Decision-making can be entirely explained by neuron activity.
  • Physical determinism: All events are the result of particle interactions governed by deterministic laws of physics.
• Argues that modern findings in physics (esp. quantum theory) undermine hard determinism.

7. Physics, Quantum Theory & Indeterminacy (35:51–44:26)

• The universe is not strictly deterministic; quantum mechanics introduces genuine indeterminacy, even at larger scales.
• The relational interpretation of quantum mechanics aligns with the relational nature of biological agency.
  • “The upshot is that systems are not fully determined by the low level physics... the future is not written. The future really is open.” [42:37, Mitchell]
  • Mentioned: Carlo Rovelli’s book "Helgoland" as an accessible explanation.

8. Neural "Noise" and Flexibility in the Brain (44:26–49:18)

• Biological organisms and neural networks are inherently noisy—not deterministic like computers.
• This “noise,” or variability, at both molecular and network levels creates openings for flexible, context-sensitive action and decision-making.
  • “...the brain is not a deterministic machine... there’s a lot more flux and variability in the precise low-level details.” [47:06, Mitchell]

9. How "Top Down" Causation Works (49:18–54:50)

• Higher-order cognitive states (beliefs, intentions) have real causal power—‘cognition is real’.
• The brain processes and filters low-level details into meaningful, macro-level patterns that guide behavior.
  • “It's the higher level meaning of the patterns that actually has causal power in the systems.” [53:15, Mitchell]

10. The Two-Stage Model of Free Will (54:50–58:33)

• Drawn from William James, this model proposes:
  1. Generation of possibilities (somewhat random, creative)
  2. Conscious selection among them (evaluation of options)
• The brain regulates how “wide” or exploratory this process is depending on context.
  • “There are systems in the brain that will raise the temperature of that search mechanism and suggest some wider kind of range of options... So we can, in a sense, choose to modulate the randomness...” [56:33, Mitchell]

11. The Present as Duration—Room for Choice (58:33–60:50)

• The present isn’t a time “instant” but has duration—allowing for flexible responses, not pre-determined replays.
  • “...the time during which the indefinite becomes definite... the action of decision making in the present that is really us exercising our own agency...” [59:11, Mitchell]
• Philosophical thought experiments about deterministic replay of choices miss the reality of temporal flux and possibility.

12. Introspection, Metacognition, and Human Agency (61:21–64:13)

• Humans can think about their own thinking, modify their desires, and choose new goals—contrary to arguments that we simply “cannot choose what we want.”
  • “We talk to each other about our reasons... in humans, this final stage of evolution... is the evolution of metacognition... That, for me, justifies... the term free will.” [63:31, Mitchell]

13. Rejecting Mystical Dualism and Embracing Cognitive Realism (64:24–67:09)

• Human agency doesn’t require anything mystical or supernatural—just the right organizational patterns in biological systems.
• Mitchell coins “cognitive realism” to describe the position that cognition and its causal power are real, not mere epiphenomena.
  • “Cognition is real. It’s not an epiphenomenon... I reverse that. I say, no, those neurons firing have causal power in the system only by virtue of what they mean. If they meant something else, different things would happen.” [67:04, Mitchell]

14. On Emergence, Top-Down Organization, and Evolution (67:09–72:47)

• Rejects vague uses of “emergence.” Effective causation in brains and life is explained by top-down organization and evolutionary “design.”
• Organisms are “causal capacitors”—embodying stored knowledge and agency through both evolutionary history and individual development.

15. Practical Implications for Neuroscience, Interdisciplinarity, and Students (74:04–77:42)

• Encourages students/scientists to read widely and avoid narrow conceptual ruts.
• Building bridges between neuroscience, philosophy, genetics, and physics is essential for fuller understanding.
  • “Read outside your discipline... sometimes getting inspiration from some other field can be really useful.” [74:08, Mitchell]

Notable Quotes & Memorable Moments

• On Agency as a Biological Phenomenon:

  “The story of agency is the story of life itself.” [13:31, Dr. Campbell paraphrasing Mitchell]

• On the Evolutionary Function of Agency:

  “Natural selection ensures that all of the interrelations of all their components... are aimed at persistence simply because if they weren't, that thing wouldn't be here.” [15:16, Mitchell]

• On Cognitive States as Real Causes:

  “Cognition is real. ...those neurons firing have causal power in the system only by virtue of what they mean. If they meant something else, different things would happen.” [01:00, 67:04, Mitchell]

• On the Ephemerality and Duration of the Present:

  “We should think of time as having... periods of duration, not instants that have zero duration... it's the time during which the indefinite becomes definite.” [58:33, 59:11, Mitchell]

• On the Limits of Reductionism and Emergence:

  “The strategy doesn't emerge from the way that players move. The strategy is imposed top down and constrains the way the players move.” [67:33, Mitchell]

• On Metacognition and Human Exceptionality:

  “We can act for our reasons. We can inspect those reasons, ...choose new goals, policies and commitments... that really do make us special in the living world.” [63:31, Mitchell]

Timestamps for Key Segments

• Intro and (Post-Ads) Start of Content: [01:00]
• Mitchell’s Background and Motivation: [04:13–09:35]
• Evolutionary Origins of Agency: [10:04–22:20]
• Agency in Bacteria and Simple Life: [22:20–29:27]
• Physical Determinism and Quantum Theory: [35:51–44:26]
• Neural Basis of Choice and "Top Down" Causation: [44:50–54:50]
• Two-Stage Model of Free Will: [54:50–58:33]
• The "Present" and Dynamic Agency: [58:33–60:50]
• Cognitive Realism and the Meaning of Causation: [64:24–67:09]
• Practical Takeaways and Advice for Students: [74:04–77:42]

Conclusion: Why Does This Matter?

Mitchell’s work reframes the free will debate by tying agency to the very roots of life itself—making choice an evolutionary achievement rather than a mystical illusion. By dispelling both hard determinism and dualism, and by insisting on the legitimacy of cognitive causation, he argues for a scientifically grounded yet deeply meaningful understanding of what makes us agents—capable of real, consequential choice.

Recommended for listeners/readers interested in:

• Neuroscience, philosophy of mind, evolutionary biology
• Debates on free will, determinism, consciousness
• The intersection of science and humanities

(Original language and tone faithfully maintained. Advertisements and non-content sections omitted.)