O livre-arbítrio é real?

critiques of Benjamin Libet's readiness potential experiments and the role of the 'veto' power

Benjamin Libet’s 1983 experiments on the "readiness potential" (RP)—or *Bereitschaftspotential*—are foundational to the cognitive neuroscience of free will. Because Libet found that unconscious neural activity (the RP) preceded subjects' conscious awareness of their urge to move (a moment termed 'W') by roughly 350 milliseconds, his work was widely popularized as scientific proof that the brain decides before the conscious mind does. However, modern neuroscience and consciousness studies heavily critique this deterministic interpretation. A primary objection is ecological validity: as philosopher Alfred Mele and others point out, Libet-style tasks rely on "low-stakes, contentless actions" (like arbitrarily flexing a finger) which fail to represent the complex, reason-responsive decision-making characteristic of human agency. Furthermore, researchers such as Aaron Schurger have fundamentally reinterpreted the RP. Through an "accumulator model," Schurger argues that the RP may not be an unconscious decision at all, but rather a reflection of spontaneous "neural noise" accumulating toward a motor threshold. Libet himself resisted total determinism, positing that conscious will retains a "veto" power over unconscious impulses. He coined the term "free won't" to describe a 100–200 ms window during which a person can consciously suppress or abort a movement before it is executed. Recent studies, such as Schultze-Kraft et al. (2016), have empirically tested this, demonstrating that humans can indeed cancel movements after the RP begins, up until a neural "point of no return" just before movement onset. Yet, the precise nature of this veto remains debated. Some recent neuroscientific literature suggests that the decision to abort an action is itself preceded by antecedent neural activity, complicating the idea of a purely conscious intervention. Ultimately, the contemporary discipline largely rejects the idea that Libet disproved free will, increasingly viewing early neural signals not as a denial of agency, but simply as evidence that "agency has a mechanism".

• jneurosci.org
• researchgate.net
• reddit.com
• wikipedia.org
• mindmatters.ai
• youtube.com

Madhyamaka arguments against the existence of a permanent agent and the concept of dependent origination

Within Mahayana Buddhism, the Madhyamaka ("Middle Way") tradition firmly rejects the existence of a permanent agent, core, or soul by appealing directly to the doctrine of dependent origination (*pratītyasamutpāda*). Founded by the 2nd-century Indian philosopher Nāgārjuna, Madhyamaka posits that all phenomena arise strictly in dependence upon multiple causes, conditions, and parts. Because entities are entirely relational, they completely lack independent, unchanging, or inherent existence (*svabhāva*). Nāgārjuna systematically deconstructs the notion of a permanent agent in his foundational text, the *Mūlamadhyamakakārikā* (Fundamental Verses on the Middle Way). He argues that if an agent possessed intrinsic, permanent nature, it would be static, self-contained, and fundamentally unable to perform actions, undergo change, or interact with reality. Thus, the ultimate nature of a person is emptiness (*śūnyatā*)—they are "empty" of intrinsic selfhood. As Nāgārjuna elegantly states, "That which is dependently co-arisen / Is explained to be emptiness". Madhyamaka philosophy resolves the apparent tension between "emptiness" and ethical agency through the framework of the Two Truths. Ultimately, a permanent agent does not exist; however, a conventional self practically exists as a dependently originated stream of psycho-physical aggregates. Madhyamaka thinkers, including Nāgārjuna and his prominent 7th-century commentator Candrakīrti, argue that the psychological habit of reifying this conventional self into a permanent entity is the root of human suffering. By dissolving the illusion of a permanent agent, the practitioner does not fall into nihilism, but rather deeply appreciates the interconnected nature of existence. For Nāgārjuna, grasping this interdependence is synonymous with spiritual awakening. As he declares at the end of the 24th chapter of the *Mūlamadhyamakakārikā*: "Whoever understands dependent origination understands suffering, its cause, its cessation and the path". In Madhyamaka, dependent origination and emptiness are two sides of the same coin, charting a "middle path" between eternalism and nihilism.

• sjsu.edu
• scribd.com
• nondualitymelbournebuddhistperspective.com
• stanford.edu
• buddhistinquiry.org
• emptinessteachings.com

Conway and Kochen's Strong Free Will Theorem and its implications for particle indeterminism

In the context of modern physics and the interpretation of quantum mechanics, John Conway and Simon Kochen’s "Free Will Theorem" (first published in 2006, followed by "The Strong Free Will Theorem" in 2009) offers a profound mathematical argument regarding particle indeterminism. Drawing upon Bell's Theorem and the Kochen-Specker paradox, the Princeton mathematicians present a rigorous challenge to deterministic "hidden variable" theories. The Strong Free Will Theorem posits a conditional relationship between human experimenters and quantum particles. It dictates that if experimenters possess "free will"—defined strictly as the ability to make measurement choices that are not entirely pre-determined by the past history of the universe—then the particles being measured cannot have pre-determined responses. As Conway and Kochen famously state, "if indeed we humans have free will, then elementary particles already have their own small share of this valuable commodity". The proof relies on three distinctive axioms, termed *SPIN*, *TWIN*, and *MIN*. *SPIN* dictates that measuring the squared spin of a spin-1 particle in three orthogonal directions always yields two 1s and one 0. *TWIN* assumes that two entangled particles will exhibit perfectly correlated spins. In their 2009 "Strong" revision, Conway and Kochen replaced an earlier axiom (*FIN*) with *MIN*, a weaker assumption requiring only that two space-like separated experimenters can make their measurement choices independently of one another. Given these axioms, the theorem proves that "the particle's response (to be pedantic – the universe's response near the particle) is not determined by the entire previous history of the universe". For the discipline of physics, this implies that no deterministic relativistic theory can fully explain quantum phenomena. Rather than dismissing particle behavior as simply random, Conway and Kochen frame this indeterminism as an intrinsic, foundational freedom—suggesting that the macro-level free will humans experience is ultimately rooted in this fundamental unpredictability at the quantum scale.

• wikipedia.org
• medium.com
• jamesowenweatherall.com
• ucsd.edu
• arxiv.org
• arxiv.org
• researchgate.net

the paradox of Tzimtzum and human autonomy in the Zohar and Lurianic Kabbalah

In Jewish mysticism, particularly within 16th-century Lurianic Kabbalah, the relationship between divine omnipresence and human autonomy presents a profound theological paradox. The central question asks: If the Infinite God (*Ein Sof*) is all-encompassing and fills all existence, how can a finite, physical world and human free will exist without being "utterly nullified within their source"? The tradition resolves this tension through the doctrine of *Tzimtzum* (divine contraction or concealment), a framework developed by Rabbi Isaac Luria (the Ari) and transmitted through texts like Hayyim Vital's *Etz Chaim*. Luria posited that to make room for independent creation, God performed an act of self-limitation, withdrawing His infinite light (*Ohr Ein Sof*) to create a *chalal panui* (vacated space). Crucially, this contraction is overwhelmingly understood by later commentators not as a literal spatial withdrawal—since God remains omnipresent—but as a "concealment or veiling of His direct presence". By "dimming" the infinite light, God engages in an act of profound divine humility, making space for something other than Himself to exist. This purposeful concealment is the absolute prerequisite for human autonomy. By stepping back to allow for an "Other," God establishes a domain defined by free will. As modern scholars describe it, this creates a sacred space "to err, to fall, to believe, to doubt, to cry, to laugh". Furthermore, this autonomy is inextricably linked to cosmic responsibility. Following the *Tzimtzum*, a subsequent cosmic catastrophe occurred known as *Shevirat HaKelim* (the Shattering of the Vessels), causing sparks of divine light to become trapped in the material world. The hidden nature of the divine presence gives humans the authentic freedom to choose good or evil. Humanity's ultimate exercise of this autonomy is *Tikkun* (repair)—using our free will to elevate these scattered sparks and restore the cosmos. Ultimately, Lurianic Kabbalah teaches that the paradox of divine absence is an illusion deliberately engineered to empower human agency and make humanity a partner in creation.

• wikipedia.org
• substack.com
• sefaria.org
• syncreticontodynamics.com
• rachav.org

Chrysippus's cylinder analogy and the distinction between internal and external causes in causal determinism

Within the tradition of Greek Stoicism, the universe is governed by strict causal determinism (or "fate"), where every event is the inevitable result of prior causes. However, the Stoics were compatibilists; they argued that determinism does not negate human agency or moral responsibility. To defend this position, Chrysippus of Soli—the highly influential third head of the Stoic school—developed his famous "cylinder analogy". Because Chrysippus's original writings are lost, this argument is primarily preserved by later classical figures such as Cicero (in *On Fate*) and Aulus Gellius (in *Attic Nights*). The analogy asks us to imagine a cylinder being pushed down a steep hill. The push initiates the movement, but the object rolls specifically because it is cylindrical. If the object were a cone or a cube, the same push would result in a different motion—spinning or sliding. This physical metaphor illustrates Chrysippus’s vital distinction between **external** and **internal** causes: * **External Causes:** Termed "auxiliary and proximate" causes by Chrysippus, these correspond to the initial push. In human life, they represent external stimuli or "impressions" that impinge upon the mind from the outside world. * **Internal Causes:** Termed "complete and primary" (or principal) causes, these correspond to the rollable shape of the cylinder. In human terms, this is our intrinsic character, internal constitution, and capacity for rational "assent" (which later Stoics like Epictetus linked to *prohairesis*, or volition). While an external impression is a necessary trigger for human action, it is not sufficient to dictate our exact response. As Aulus Gellius records Chrysippus's argument, the cylinder "speeds onward, not because you make it do so, but because of its peculiar form and natural tendency to roll". Therefore, our actions are ultimately determined by our own internal nature. Because the principal cause of human behavior stems from within, the Stoics concluded that our choices are genuinely "up to us," preserving our moral responsibility within a fated cosmos.

• stanford.edu
• substack.com
• medium.com
• donaldrobertson.name
• oup.com
• wku.edu
• reddit.com

computational irreducibility and the emergence of agency in deterministic algorithmic systems

Within the framework of information theory and digital physics, the emergence of agency in deterministic systems is fundamentally linked to the concept of **computational irreducibility**. This tradition posits that strict determinism is entirely compatible with free will and autonomy. Rather than relying on quantum randomness or metaphysical interventions, agency arises because the evolution of complex algorithmic systems cannot be mathematically shortcut. Stephen Wolfram, a central figure in this discipline, established in his 2002 text *A New Kind of Science* that simple deterministic systems, such as Class 4 cellular automata (e.g., Rule 110), produce behavior so complex that their future states are formally unpredictable. The only way to know the outcome of the system is to execute the computation step-by-step. Wolfram argues that this dynamic bridges determinism and autonomy, stating, "And the key, I believe, is the phenomenon of computational irreducibility... it is this, I believe, that is the ultimate origin of the apparent freedom of human will". A distinctive concept in this subfield is **computational sourcehood**. This principle asserts that an agent acts as the irreducible origin of its own behavior because no external observer can predict its choices faster than the agent can compute them. Any successful prediction would require a near-perfect simulation of the agent's internal structure. Recent formalizations, such as Azadi’s 2025 research on "emergent agency," argue that algorithmic undecidability creates a necessary "information gradient". In these models, a system achieves operational closure and genuine autonomy precisely because its interaction with the environment generates "incompressible" bits of novel information at each step. Ultimately, this tradition asserts that agency does not require breaking physical laws. Instead, an agent acts autonomously by "'being the computation' in real time, a process which cannot be pre-determined". By viewing the universe as a computationally irreducible engine, determinism becomes the very mechanism that protects an agent's internal autonomy from external prediction.

• emergentmind.com
• stanford.edu
• turingchurch.net
• nih.gov
• arxiv.org
• arxiv.org

the concept of Ikhtiyar and the relationship between the human heart and Divine Will in Ibn Arabi's metaphysics

Within the metaphysical tradition of Islamic Sufism, the dialectic between human free will (*ikhtiyar*) and Divine Will is profoundly articulated by Muḥyī al-Dīn Ibn ʿArabī (d. 1240). Operating under the paradigm of *waḥdat al-wujūd* (the Oneness of Being), Ibn ʿArabī resolves the tension between determinism and free choice by linking human agency to the "immutable entities" (*aʿyān thābita*)—the eternal archetypes of all creation residing within God's knowledge. God’s Will manifests exactly according to the unique, eternal predispositions of these entities. Therefore, while God is the ultimate actor, human beings genuinely experience *ikhtiyar* because the Divine decree simply unfolds the reality of what they inherently are. The focal point of this divine-human interaction is the spiritual heart (*qalb*). In texts such as *Al-Futūḥāt al-Makkiyya* and *Fuṣūṣ al-Ḥikam*, Ibn ʿArabī highlights that the word *qalb* shares an Arabic root with *taqallub*, meaning "fluctuation" or "transmutation". The heart is not static; it constantly shifts to receive the unceasing, ever-renewing theophanies (*tajallī*) of the Divine Will. As William C. Chittick observes in his foundational study *The Sufi Path of Knowledge*, a core maxim of Ibn ʿArabī’s thought is, "He who knows himself knows his Lord". When the heart is purified of the lower ego (*nafs*), it transforms into a flawless mirror capable of reflecting Divine light and intuitive knowledge (*ʿilm ladunnī*). For the realized Sufi, the ultimate spiritual goal is not to assert independent *ikhtiyar*, which would falsely treat the individual as an autonomous entity and contradict the fundamental unity of God (*tawhid*). Rather, the highest state requires the believer to "abandon self-choice". As Ibn ʿArabī describes the loftiest tier of saints: "Stripped of his ego, he has renounced all free will (*ikhtiyar*)". Through this absolute surrender, the purified *qalb* does not so much lose its agency as it perfectly aligns with the Divine, acting as a conscious participant (*ishtirak*) in God's continuous unfolding of creation.

• quora.com
• bahai-library.com
• archive.org
• medium.com
• researchgate.net
• uleth.ca
• scribd.com
• gwu.edu
• academia.edu
• scribd.com