Neuroscience and free will

From: jimruttshow8596

Robert Sapolsky, an American neuroendocrinology researcher and author, holds a strong incompatibilist view on free will, asserting that it does not exist [00:02:47]. His most recent book, “Determined: A Science of Life Without Free Will”, delves into this famously complex topic [01:54:30]. Sapolsky considers his position, which states “there’s no free will whatsoever,” to be at the “lunatic fringe” [00:02:30], as most people and philosophers do not share this absolute stance [00:19:37].

The “Turtles All the Way Down” Argument

Sapolsky frames his argument using the “turtles all the way down” anecdote, where every event is caused by a prior event, leading back indefinitely [00:03:29]. He contends that claiming an action can occur “without any causes whatsoever” is scientifically incorrect and ridiculous [00:04:47]. His book aims to present a comprehensive picture from various disciplines to close off any “escape valve” for free will [00:05:07].

He explains that understanding why someone does something requires examining a continuous “arc of influences” [00:07:07], ranging from:

• Immediate Brain Activity: What was happening in their brain “just now” [00:05:27].
• Current Physiological State: Factors like being tired, stressed, hungry, or euphoric, which affect brain function [00:05:34].
• Hormone Levels: Daily hormone levels influencing brain sensitivity [00:05:40].
• Recent Experiences: Trauma or positive events in previous months that alter brain workings [00:05:47].
• Developmental History: Adolescence, childhood, and even fetal life, which significantly shape brain construction [00:06:06].
• Genetics: Inherited genes [00:06:06].
• Ancestral Culture and Environment: The culture and ecosystems of ancestors, influencing upbringing [00:06:23].

Sapolsky argues that when one looks closely at this continuous chain, “there is not a crack anywhere in there in which you can shoehorn in a kind of free will that requires you to invoke magic” [00:07:16].

Examples of Influences

Sapolsky provides surprising examples of how behavior is underlined by often unrecognized influences:

• Environmental Odors: People become more politically and socially conservative when filling out questionnaires in a room smelling of “stinking garbage” [00:09:30], whereas a smell of freshly baked chocolate chip cookies makes them more generous [00:10:17]. This occurs without conscious awareness [00:10:29].
• Fetal Stress Hormones: Chronic maternal stress during pregnancy leads to elevated stress hormones in the fetus, resulting in a larger and more reactive amygdala in the child [00:11:44], making them more likely to perceive neutral faces as threatening [00:12:05].
• Ancestral Infectious Disease Load: Cultures whose ancestors faced high infectious disease loads 400 years ago tend to be less welcoming to immigrants and novelty today [00:13:07], influenced by early childhood training [00:13:26].
• Blood Glucose Levels: Lower blood glucose levels impair the prefrontal cortex’s ability to exert impulse control, making individuals more prone to “dumbass impulsive” actions [00:34:09].

Sapolsky challenges the idea that these are merely “urges” or “influences” that don’t add up to complete determination, arguing that every single factor contributes to the ultimate outcome [00:07:54].

Categorizing Views on Free Will

Sapolsky outlines four main positions on free will:

1. Libertarians (philosophical): Believe in a completely undetermined world where individuals are entirely free in their actions [00:18:35]. Sapolsky dismisses this as paid “virtually no attention to” by most philosophers [00:18:47].
2. Undetermined World with Responsibility: Those who believe the world is undetermined but people are still held responsible for their actions [00:19:02]. Sapolsky finds this even less coherent [00:19:02].
3. Compatibilists: The majority (90-95%) of philosophers who reconcile free will and responsibility with a deterministic world [00:19:41]. They accept that we are biological machines governed by physical laws, but still find room for free will [00:19:45].
4. Incompatibilists (Sapolsky’s stance): Believe in a totally deterministic world, meaning there is no free will and thus “notions of responsibility make no sense at all” in theory [00:19:56]. This view is shared by a small majority of brain scientists but only about 2% of philosophers [00:21:01].

Sapolsky rejects the legal system’s criteria for culpability—intent, understanding consequences, and perceived choice [00:24:12]—because it fails to ask the crucial question: “where did that intent come from?” [00:24:50]. He likens this to reviewing a movie having only seen the last three minutes [00:24:42].

Agency vs. Free Will

When discussing agency, Sapolsky distinguishes between mere physical responsibility (e.g., bumping into someone when tripping) and the intuitive philosophical sense of being “the captain of your ship” [00:27:02]. He argues that in the latter sense, agency is synonymous with free will, and thus, “there is no Captain” [00:27:07]. Even seemingly complex decisions, like evaluating risks in a confrontation, are outcomes of accumulated deterministic influences, such as cultural background and past experiences [00:30:10].

Neuroscience and Consciousness

Phineas Gage

A foundational case in neuroscience illustrating the brain’s role in personality and moral behavior is that of Phineas Gage [00:34:45]. Gage, a railroad foreman in the 1840s, suffered a traumatic brain injury when an iron pole shot through his prefrontal cortex (PFC) [00:36:05]. The PFC is the most recently evolved part of the human brain, responsible for impulse control, gratification postponement, and inhibiting “animal urges” [00:36:32]. After his injury, Gage, previously a responsible man, became “abusive, alcoholic, bully, sexually disinhibited” [00:37:56].

Sapolsky emphasizes that such drastic changes in personality and self-discipline don’t require gross brain damage. Subtle influences like:

• Fetal Stress Hormones: Can lead to a less metabolically active PFC [00:39:16].
• Childhood Environment: Growing up in a violent neighborhood can result in fewer synaptic connections in the PFC [00:39:27].
• Poverty: Can lead to a smaller PFC by age five [00:39:36].

These factors cumulatively explain an individual’s capacity for emotional control, illustrating that actions are products of biological and environmental history, not uncaused choices [00:39:54]. People often “confabulate” explanations for their behavior after the fact, unaware of the true underlying causes [00:43:31].

Libet’s Experiment and “Free Won’t”

Benjamin Libet’s experiment famously showed that brain activity (readiness potential) precedes conscious awareness of a decision to act [00:48:31]. This led many to conclude that the brain decides before “you” consciously do [00:49:13]. Sapolsky, however, finds the resulting debate about milliseconds of decision-making “totally boring” [00:50:07]. His core critique remains: the experiment doesn’t address “where did that intent come from in the first place?” [00:50:30].

The concept of “free won’t” (the ability to veto an action) is also dismissed by Sapolsky [00:55:00]. He argues that the decision to inhibit an action is subject to the exact same deterministic influences as the decision to act [00:57:00].

Consciousness’s Role

Sapolsky regards consciousness as irrelevant to the question of free will [00:53:58]. He notes that while consciousness is fascinating, much of what it does is try to explain “why did I do that just now” after the fact, rather than being the causal agent [00:54:16].

Dispelling Illusions of Free Will

The Myth of Grit

Sapolsky criticizes the “myth of grit” [00:59:12], tenacity, and self-discipline as falsely dichotomized from biological predispositions [00:59:30]. Society praises “grit” as a magical, uncaused quality, distinct from “biological stuff” like coordination or memory [01:00:18]. Sapolsky argues that tenacity and self-indulgence are “exactly as biological” as any other trait [01:01:52], rooted in the prefrontal cortex and shaped by the same “arc of influences” [01:03:00].

He references the “marshmallow test” [01:04:48], where a child’s ability to delay gratification at age five correlates with future health, earnings, and education [01:06:36]. This seemingly volitional act is predictable from differences in brain function and early life experiences [01:06:12]. For Sapolsky, there’s “no difference than being 7 foot 4” [01:07:32]; both are outcomes of deterministic factors.

The Illusion of “Key Cusp Decisions”

The idea that individuals make a few “key cusp decisions” that define who they become (e.g., choosing to go to college) is also challenged [01:10:05]. Sapolsky asks why someone makes that particular choice, again tracing it back to genetic makeup, upbringing, influential teachers, and other circumstances. The “inspiration” to make a life-altering choice is itself an outcome of prior deterministic events [01:12:42].

Scientific “Escape Valves” and Their Demise

Sapolsky also addresses scientific concepts sometimes invoked to support free will:

• Deterministic Chaos: He agrees that deterministic chaos, where small changes in initial conditions lead to vastly unpredictable outcomes, does not provide room for free will [01:14:12]. Unpredictability is not the same as being uncaused.
• Quantum Indeterminacy: While acknowledging that the universe’s fundamental nature (deterministic vs. stochastic) is still debated in quantum mechanics [01:15:17], Sapolsky dismisses it as a source of free will for three reasons [01:16:15]:
  1. Scale: Quantum effects are too small (subatomic) to impact macroscopic brain activity significantly [01:16:46].
  2. Randomness vs. Will: Even if quantum effects scaled up, they would produce randomness, not stable, purposeful behavior [01:17:31].
  3. Harnessing: The idea that a “conscious you” could “harness” quantum indeterminacy at a subatomic level is “idiotic” and requires a basic rejection of how physics functions [01:18:15]. The brain is too “moist and warm and messy” for quantum coherence to be maintained [01:20:19]. This is often leveraged in “New Age Quantum” theories [01:18:22].
• Emergent Complexity: Sapolsky loves the concept of emergence—where complex properties arise from simple interactions of many elements (e.g., wetness from water molecules, ant societies from individual ants, consciousness from neurons) [01:24:03]. However, he argues that theories trying to derive free will from emergence fail because they require the individual building blocks (e.g., neurons) to “suddenly get smarter” or “work differently” once part of a larger system [01:25:52]. This violates the core principle of emergence, where the individual components retain their simple rules [01:25:47].

While acknowledging “downward causality” (macro-level decisions affecting micro-level elements, like rolling a stone down a hill affecting its electrons) [01:29:02], Sapolsky distinguishes this from “harnessing” elements to make them act outside their physical laws [01:30:08]. Abstract concepts like “honor” or “law and order,” while influencing behavior, are still manifestations of the deterministic brain and culture, not independent agents [01:29:51].

Implications of No Free Will

Sapolsky addresses the common concern that rejecting free will would lead to societal chaos [01:39:15]. He argues the opposite: a world without belief in free will would be “a much more humane place” [01:39:17].

• Ethics: Studies show that individuals who have deeply considered the absence of free will are just as ethical as those who strongly believe in it [01:40:14]. Casual rejection of free will might lead to short-term moral lapses, but deep philosophical engagement does not [01:39:44].
• Change: The idea that “nothing can ever change” without free will is false [01:41:12]. People change, but they are “changed by the circumstances that put you in that place” [01:41:41].
• Justice and Responsibility: Society can still contain dangerous individuals (like a car with broken brakes) by quarantining or containing them without invoking moral judgment or punishment beyond what is necessary for safety [01:43:59]. Similarly, competent neurosurgeons can be recognized and utilized without attributing their skill to a “better soul” [01:44:25].
• Compassion: Rejecting free will promotes compassion by recognizing that individuals are shaped by factors beyond their control (e.g., genetic predispositions to obesity, rather than “lack of willpower”) [01:45:23]. It removes the “crappy screwed world” where people are judged and punished for things they couldn’t control [01:45:57].

Sapolsky concludes that while the idea of no free will might initially feel like a “bummer,” it is ultimately “fabulous” and will lead to a more “humane Planet” [01:46:13], much like abandoning the belief in witches improved society [01:46:51].