In the 1970s, the neurologist Benjamin Libet sought to determine the precise timing between conscious awareness of a voluntary decision and electrical activity in the brain.i
Common sense normally expects that the awareness of a decision to act precedes the neural activity allowing the action itself. The very surprising result of Libet’s experiments is that it seems to be the opposite…
These experiments, which are now famous, involved the observation of the temporal link between the subjective sensation associated with the decisional « threshold » (the moment of « awareness » of the decision) and the neural activity associated with the motor movements that are supposed to follow this decision.
The results of Libet’s experiments, which are highly paradoxical and have been confirmed many times, have been commented on by neuroscientists, mostly as a confirmation of the internal autonomy of the brain with respect to consciousness, and subsequently as a confirmation of the absence of free will…
These results can be summarized as follows: unconscious cerebral events precede by a time that can vary from several tenths of a second to several seconds, the conscious sensation of having made a voluntary decision to perform a motor action (for example, pressing a button)ii.
These « unconscious brain events » are observable in the form of electrical potentials, called « readiness potentials » or « premotor potentials ». These electrical potentials measure the activity of the motor cortex and of the brain region involved in the preparation of voluntary muscle movements.
For most commentators, Libet’s experiments confirm the absence of any human free will, because, according to them, they highlight the fact that the brain itself autonomously produces « preparatory potentials » for motor movement before the decision to act reaches consciousness.
Everything happens, therefore, as if the « consciousness of acting » were a simple « illusion », consecutive to the decision taken unconsciously by the brain itself, independently of any conscious involvement of the subjectiii.
In other words, unconscious neurological processes would first provoke the motor act (its preparation and initialization) and then the « conscious » sensation in the subject of having taken the decision to act, by his own (« conscious ») will.
The general conclusion drawn by Libet from these observations is that brain processes determine decisions, which are then perceived as subjective by the brain through the phenomenon of consciousness.
Libet does, however, consider the notion of a veto – the ability of « consciousness » to block an act that is being prepared or even already committed – as possible. This would be the only space of free will or « free will » that remains at the disposal of « consciousness », that of blocking the action, always possibly possible in the very short time (a few hundred milliseconds) that takes place between the subjective perception of the decision and the execution of the act itself.
The deterministic interpretation of Libet’s findings, culminating in the radical questioning of the idea of free will, is currently largely predominant among neuroscientists and biologists. Biologist Anthony Cashmore summarizes the majority thinking by saying that belief in free will « is nothing less than a continuation of belief in vitalism »iv.
There are some skeptics, however, who still resist.
Some question the implicit assumption that decisions must be initiated by consciousness in order to be considered « free ». The idea is that ultimately free will is not related to consciousness but only to « control », and that one could assume the existence of a « pre-conscious free will « .v
Others consider that the role of the experimental context should not be neglected, in particular the conscious choice, made by the subjects undergoing the experiments, to pay special attention to bodily signals which usually remain subconscious.
On the other hand, it must be emphasized, as Alexander Wendt does, that no one really knows what « readiness potentials » are, or how they can be the cause of a behaviorvi. For example, they might only serve to present the occurrence of a choice (rather than embodying the choice itself), which would amount to saving the idea of free will.
Alexander Wendt believes that quantum perspectives potentially renew the debate around Libet’s experiments, but that precisely they have never been considered for their interpretation until now.
However, he mentions Roger Penrose’s opinion that these results show the inadequacy of the classical conception of time. Penrose suggests that Libet’s results could be explained by a kind of « retro-causation » or « advanced action » that is allowed by quantum theory.vii
For his part, Henry Stapp establishes a link between the Libet experiments and the Einstein-Podolsky-Rosen paradox on the question of non-locality. Stuart Hameroff, based on his own theory of the quantum brain, believes that « non-local temporality and the backward time referral of quantum information [advanced action] can provide real-time conscious control of a voluntary action ».viii
The most argued criticism of Libet’s results on the basis of quantum theories is that of Fred Alan Wolfix who also relies on the quantum notion of temporal non-locality. But he adds considerations related to the evolutionary advantage. Being able to sense an impending experience has an obvious value in terms of survival chances in case of danger, especially if this pre-awareness capacity allows to gain more than half a second, without waiting for full consciousness to be acquired.
Furthermore, he proposes the image of the brain as « a giant delayed choice machine ».
Finally, Wolf shows that the time-symmetric quantum perspective can explain an important anomaly in Libet’s experiment: the subjective anti-dating. In fact, not only does the quantum perspective account for it, but it predicts it.
Concluding his study on this question, Alexander Wendt clearly states his rejection of deterministic and materialistic theories: « So my point is not that human behavior cannot be made more predictable – more ‘classical’ – through coercion, discipline, or incentives, but rather that no matter how successful such schemes are, there is a spontaneous vital force in the human being that fundamentally eludes causal determination »x.
Would Wendt demonstrate « vitalism »?
I would opt for the belief in an irreducible entity, present in the depths of the human being.
By consulting the multi-millennial traditions of humanity, one can note the multiple ways in which one has given an account, since the dawn of humanity, of this irreducible entity, constitutive of our deepest being, this absolute, secret, hidden, abyssal entity, which stands in the depths of the being, and which is infinitely more original than what we call the « me », or the « consciousness ».
The Veda calls it ātman, the Hebrew Bible uses several words, which have their own nuances, נִשְׁמַת (neshmah), נֶפֶשׁ (néfèsh), רוּחַ (rouaḥ), the Greeks speak of νοῦς (noûs) and ψυχή (psyche).
To make an image, we could call it the « self », the « soul », or the « fine point of the spirit ». The word is not the most important thing, it is the idea itself that is important, – the idea that all cultures have known how to express it in their own way, by means of words that have all in some way their own genius.
Only modern science, positivist, causalist (but also with a strong materialist and determinist tendency) has not only no word but no conception of this « entity », by nature immaterial (thus obviously escaping EEG, fMRI, PET Scan, TMS…), and above all conceptually elusive in the frame of reference of science, namely the experimental and rationalist epistemology.
I would only like, in the framework of this short article, to indicate briefly, but forcefully, that the results of Libet’s experiment could perfectly well be interpreted in a way that is radically opposed to the conventional interpretation (causalist, materialist, physicalist… and determinist).
Let us assume for a moment, for the purpose of establishing my hypothesis, that:
Far below the immense, abysmal depths of consciousness, far beyond even that underlying continent, the Unconscious, which Sigmund Freud and C.-G. Jung, the first explorers, the first cartographers, only scratched the surface of, there exists, for each of us, an entity that I will call « ι » (the Greek iota).
Why this name?
This entity, named » ι « , summarizes in a way a great number of concepts already consecrated by the tradition.
A few expressions can be quoted, chosen in their multiplicity: scintilla animae (« spark of the soul »), scintilla conscientiae (« spark of the conscience »)xi, « fine point of the soul » (Teresa of Avila), « living flame » or even « hair » (John of the Cross)xii.
In De Veritate, Thomas Aquinas states: « Just as the spark is the purest thing in fire and the highest thing in the judgment of the conscience ».xiii
Master Eckhart also uses the image of the spark, but to refine it by reducing it to freedom itself, freedom seen as an absolutely one and simple entity:
« This little stronghold of the soul, I said it was a spark, but now I say this: it is free of all names, devoid of all forms, absolutely uncluttered and free, as God is uncluttered and free in himself. He is as absolutely one and simple as God is one and simple. »
Francis de Sales speaks of « the point of the spirit », « the depth of the soul » or « the high region of the spirit ».
To gather this bundle of approaches, in a simple and unique image, I propose to concentrate them in this » ι « , this Greek iota. Totally immaterial, infinitely elusive, » ι » is the initial spark that makes you yourself, and not another. It is the first germ around which the successive layers of consciousness and being have slowly accumulated, since conception, and which have not ceased, day after day, to grow, to unfold, to become more complex by epigenesis. This » ι » is the tiny seed, resisting to all the storms, to all the winds, to all the storms, and which, stubborn, trusting, ineradicable, pushes at every moment in the solitude of its own I-ness. This » ι » remains , as I remain. The » ι » remains, but in order to leave, to fly towards the top, towards the elsewhere, towards the absolutely-other.
Let us consider now the relation between the » ι « , the consciousness and the (neuronal) brain.
The » ι » holds under its calm glance the whole of the abysses of the unconscious, just like the lapping of the consciousness. The » ι » is alive, the very spark of the life. The » ι » lives and wants, freely. There is no one freer than him. What « ι » really wants, God also wants, I would even say. It is their very alliance.
What happens then in a human brain, when the « ι » of such and such a particular person, starts to « want », either to escape in urgency from a hungry tiger, or to dedicate himself to some distant goal, or to participate in a neurological experiment of the good professor Libet?
Well, the « ι » enters in quantum resonance (in a non-local and intricate way) with the whole of the receptors of its « body » (for example the micro-tubules whose putative role in the emergence of consciousness we owe to Roger Penrose and Stuart Hameroff).
This results in a rapid mobilization of the « preparation potentials », the premotor potentials acting on the motor cortex, and a parallel mobilization of the « consciousness » initiating centers (there are several of them, which function in parallel, but which are activated in conscious mode only when necessary, often remaining in subconscious mode, and most of the time in unconscious mode)
Here is my provisional interpretation of Libet’s experiments: the fact that the activation of the preparatory potentials precedes by 350ms the sensation of « awareness » has no meaning in relation to the hidden, undetectable, but implacably prevalent presence of the « ι ».
The » ι » is there. It watches. It wants. It lives. It always lives.
All the rest, the microtubules, the neurons, the cortex, the self, the consciousness, are simply its devoted, more or less obedient, skillful or sleepy, servants.
iBenjamin Libet (1985), « Unconscious Cerebral Initiative and the Role of Conscious Will in Voluntary Action », The Behavioral and Brain Sciences, 8(4), 529-566. Benjamin Libet (2004), Mind Time, Harvard University Press, Cambridge, MA.
iiBenjamin Libet found that the readiness potential appears 350-400ms before the awareness of the intention to act and 550ms before the initiation of the act itself.
iiiCf. Daniel Wegner (2002). The Illusion of Conscious Will, MIT Press, Cambridge MA.
ivQuoted by Sven Walter, « Willusionism, Epiphenomenalism and the Feeling of the Conscious Will », Synthese, 191(10), 2215-2238
vCf. Alexander Wendt. Quantum Mind and Social Science. Cambridge University Press, 2015, p. 186, Note 59.
viAlexander Wendt. Quantum Mind and Social Science. Cambridge University Press, 2015, p. 186
viiRoger Penrose (1994), Shadows of the Mind : A Search for the Missing Science of Consciousness, Oxford University Press, p. 383-390
viiiStuart Hameroff, « How Quantum Brain Biology Can Rescue Conscious Free Will », Frontiers in Integrative Neuroscience, 6, article 93, p. 14, quoted buy Alexander Wendt. Quantum Mind and Social Science. Cambridge University Press, 2015, p. 187
ixFred Alan Wolf (1998), « The Timing of Conscious Experience », Journal of Scientific Exploration, 12(4), 511-542
xAlexander Wendt. Quantum Mind and Social Science. Cambridge University Press, 2015, p. 188
xiA term coined by Jerome of Stridon
xii« The hair is the will of the soul ». John of the Cross. Spiritual Canticle B, 30,9
xiiiThomas Aquinas, De Veritate, 17, art. 2, ad. 3
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