The meaning and significance of Benjamin Libet’s studies on the timing of conscious will have been widely discussed, especially by those wishing to draw sceptical conclusions about conscious agency and free will. However, certain important correctives for thinking about mental states and processes undermine the apparent simplicity and logic of Libet’s data. The appropriateness, relevance and ecological validity of Libet’s methods are further undermined by considerations of how we ought to characterise intentional actions, conscious intention, and what (...) it means to act with conscious intent. Recent extensions of Libet’s paradigm using fMRI and decision-based tasks suffer from similar limitations. The result is that these sorts of laboratory studies of isolated, trivial, decontextualized bodily movements, in a context of extended (conscious) intentional experimental participation and cooperation, are of dubious and potentially misleading relevance to the study of agency. (shrink)

Based on his experimental studies, Libet claims that voluntary actions are initiated by unconscious brain activities well before intentions or decisions to act are consciously experienced by people. This account conflicts with our common-sense conception of human agency, in which people consciously and intentionally exert volitions or acts of will to initiate voluntary actions. This paper offers an alternative interpretation of Libet's experiment. The cause of the intentional acts performed by the subjects in Libet's experiment should not be (...) exclusively attributed to special cerebral processes; conscious intentions formed at the beginning of the experiment, when the subjects received experimental instructions, must be taken into account. In addition, what the subjects were required to report was not a conscious intention or decision to act that conventionally figures in the etiology of voluntary action, but rather a perceived effective urge to move induced by specific experimental instructions. According to the alternative interpretation, the most suitable mental term correlated with the specific brain activity that precedes conscious, self-initiated voluntary bodily movements is volition. This account is supported by recent theories of function of the supplementary motor area . Therefore, the notion that we are the authors or originators of our own actions, which is fundamental to our common understanding of free will, moral responsibility and human dignity, can be preserved. (shrink)

Free will, which is dealt with under the title of "acts of the servants" in the Kalām literature, is one of the fundamental issues of the science of Kalām. Benjamin Libet's famous experiment, which he conducted in order to seek an answer to the question of free will, caused the free will debates to move to the field of neuroscience. The logic of Libet's experiment is to compare the neural activity in the brain with the moment when a (...) person is conscious while performing a voluntary act. In Libet's subjects, it was observed that brain activity in the decision-making process started at the moment of unconsciousness. The results of this experiment have long been interpreted in neuroscience as showing that free will is an illusion. Although Libet claimed that conscious intention creates a veto effect by stopping the action at the last moment, recent studies have shown that Libet's veto solution for free will does not work. The most vocal critics of the implications of the Libet experiment from the beginning have generally been philosophers. In this article, the criticisms of the Libet experiments by names such as Marcel Brass, Alfred Mele, and Peter Ulric Tse are presented. However, especially in recent years, neuroscientist Aaron Schurger's experimental and mathematical reinterpretation of the concept of readiness potential, which is key for Libet, and his proposal of an alternative model are mentioned. The article discusses Schurger's claim that the readiness potential may not actually reflect a brain that is ready. According to Schurger, the readiness potential is just random fluctuations that already exist in the brain and is not the sole cause of decisions. In fact, it has been argued that the readiness potential is related to neural noise in the brain rather than to the decision-making process. Thanks to Schurger's critique and the new model, it became clear that the Libet experiment did not rule out free will. But it does not constitute a proof of free will either. While the subject remains a mystery, it is unthinkable for Kalām to remain aloof from these debates. The article also touches upon the views of the Jabriyya, Ash'ariyya, Maturidiyya and Mu'tazilah in Kalām regarding the acts of the servants and questions what the Libet experiment can mean for these schools. Accordingly, while Jabriyya, with its deterministic view, may correspond to an erroneous interpretation of the Libet experiment, Mutazila may be the school that will have the most difficulty in explaining the Libet experiment. As a result, it seems that the views that consider both human agency and God's creation in voluntary acts are the most accurate. Moreover, despite the lack of a clear explanation of the theory of kasb in the Ash'ariyya, the Maturidiyya's assertion that the juz'i will is uncreated and that two influences affect voluntary acts suggests that this school provides the most solid foundation for free will. In order for such discussions to proceed on a healthy basis, it is very important to follow multidisciplinary methods. In addition, as much as Kalāmists should approach scientific studies seriously, it is important that they do not adopt a completely submissive attitude in the face of scientific claims, and that they learn the relevant critiques from experts in the field. Only in this way, we believe that the scientific inferences to be made will be based on a solid ground and that Kalāmists can make serious contributions to the solution. (shrink)

Evidence that led to the hypothesis of a backwards referral of conscious sensory experiences in time, and the experimental tests of its predictions, is summarized. Criticisms of the data and the conclusion by Churchland that this hypothesis is untenable are analysed and found to be based upon misconceptions and faulty evaluations of facts and theory. Subjective referral in time violates no neurophysiological principles or data and is compatible with the theory of "mental" and "physical" correspondence.

Abstract : Libet’s famous experiments, showing that apparently we become aware of our intention to act only after we have unconsciously formed it, have widely been taken to show that there is no such thing as free will. If we are not conscious of the formation of our intentions, many people think, we do not exercise the right kind of control over them. I argue that the claim this view presupposes, that only consciously initiated actions could be free, places (...) a condition upon freedom of action which it is in principle impossible to fulfil, for reasons that are conceptual and not merely contingent. Exercising this kind of control would require that we control our control system, which would simply cause the same problem to arise at a higher-level or initiate an infinite regress of controllings. If the unconscious initiation of actions, as well as the takings of decisions, is incompatible with control over them, then free will is impossible on conceptual grounds. Thus, Libet’s experiments do not constitute a separate, empirical, challenge to our freedom. (shrink)

Benjamin Libet compared the perceived time of direct brain stimulation to the perceived time of skin stimulation. His results are among the most controversial experiments at the interface between psychology and philosophy. The new element that I bring to this discussion is a reanalysis of Libet's raw data. Libet's original data were difficult to interpret because of the manner in which they were presented in tables. Plotting the data as psychometric functions shows that the observers have great uncertainty about the (...) relative timing of events, as seen the shallow psychometric slopes. A second indication of uncertainty comes from Libet's use of three response categories, A first; B first; and A and B simultaneous. The large number of “perceptually simultaneous” responses provides a further measure of the difficulty of the judgment. There are thus a very broad range of stimulus delays in which the subject is unable to make an accurate ordering response. These points provide evidence that there is no compelling reason to invent exotic or ad hoc mechanisms to account for Libet's data since the uncertainty window is large enough to allow simple mechanism such as memory shifts. Libet argued that his data provide evidence for a backward referral in time. I argue that even though Libet's own data are weak, there are good arguments for a backward referral mechanism to help the subject make sense out of the tangled chaos of asynchronous information associated with experienced events. (shrink)

Commentary on John Searle's Article John Searle presents a philosopher's view of how conscious experience and free action relate to brain function. That view demands an examination by a neuroscientist who has experimentally investigated this issue.

Sensation elicited by a skin stimulus was subjectively reported to feel stronger when followed by a stimulus to somatosensory cerebral cortex , even when C was delayed by up to 400 ms or more. This expands the potentiality for retroactive effects beyond that previously known as backward masking. It also demonstrates that the content of a sensory experience can be altered by another cerebral input introduced after the sensory signal arrives at the cortex. The long effective S-C intervals support the (...) thesis that a duration of cortical activity of up to 0.5 s is required before awareness of a sensory stimulus is developed. (shrink)

This issue of Consciousness and Cognition presents four target articles and eight commentaries on the target articles. The present article presents comments on those commentaries, grouped into backward referral and volition categories. Regarding backward referral: I disagree with my fellow commentators and take the unpopular position of defending Libet's notion of backward referral. I join my fellow commentators in critiquing Libet's notion of a 500-ms delay. I examine several of the hypotheses suggested by other commentators for why cortical and lateral (...) meniscus stimulation give very different timing results. I suggest a simple experiment to help discriminate among the hypotheses. I comment on why temporal reordering is more likely to occur late rather than early in mental processing. Regarding Libet's volition experiments, I ask what is the root of the controversy, given the general agreement on the data. I agree with a commentator that Libet's chronotheology rather than his chronoscience is the cause of much of the controversy. Rather than joining others in criticizing Libet for his chronotheology I point out that he is making a respectable philosophical point regarding nondeterministic Free Will, but one that is easily misunderstood. I discuss two ways by which Libet's viewpoint can be brought into mainstream science. (shrink)

The chief goal of Velmans' article is to find a way to solve the problem of how conscious experience could have bodily effects. I shall discuss his treatment of this below. First, I would like to deal with Velmans' treatment of my own studies of volition and free will in relation to brain processes. Unconscious Initiation and Conscious Veto of Freely Voluntary Acts Velmans appropriately refers to our experimental study that found that onset of an electrically observable cerebral process preceded (...) the appearance of the subject's awareness of the conscious wish to act, by at least 350 msec. That indicated that the volitional process is initiated unconsciously. Velmans uses the term preconscious instead of unconscious. But, in fact, subjects have no reportable awareness or intuitive feeling that the brain has started a process before their conscious wish/urge to act appears. Unconscious initiation of the voluntary process appeared to mean that conscious free will could not actually 'tell' the brain to begin its preparation to carry out a voluntary act. (shrink)

Voluntary acts are preceded by electrophysiological (RPs). With spontaneous acts involving no preplanning, the main negative RP shift begins at about200 ms. Control experiments, in which a skin stimulus was timed (S), helped evaluate each subject's error in reporting the clock times for awareness of any perceived event.

In lieu of an abstract, here is a brief excerpt of the content:Commentary on “Free Will in the Light of Neuropsychiatry”Benjamin Libet (bio)Is Free Will Incompatible with Neuroscience?Sean Spence sets forth some interesting approaches to the issue of free will. His concepts are provocative and his marshalling of related quotations is informative.However, I shall argue with some of his crucial assumptions, in a way that affects the validity of some of Spence’s major conclusions. The latter are that “conscious experience is (...) always temporally postneural activity and thus... ‘caused’ not causal. Our ‘control’ is a sense which may be lost.... Our sense of agency is apparently illusory.”I have, of course, no quarrel with the view that even a fully voluntary act is initiated unconsciously (non-consciously). That condition was in fact demonstrated experimentally by us (Libet et al. 1983) when we found that cerebral neural activity (“readiness potential”) precedes the subject’s awareness of his/her intention or wish to act by at least 350 msec. This applied to fully self-initiated acts that occurred without “pre-planning” by the subject of when to move. (Incidentally, those finding have been replicated by others—see Keller and Heckhansen, 1990 with commentary thereon by Libet 1992, and Wong et al. 1988).However, we also found that conscious intention did precede that actual motor act by about 200 msec. That left open the potentiality for the conscious function to control the outcome of the process that was initiated in the brain unconsciously (see Libet 1985). We have all had the experience of consciously suppressing or vetoing the performance of an urge or intention to act. The 200 msec interval provides sufficient time in which the voluntary process could be stopped, before final activation of the motor area about 50 msec before the act. We were able to show that subjects could veto an act in the 100–200 msec interval before the expected time for the action.Spence dismisses this free will potentiality in the control or veto of a voluntary process. He says: “It is flawed because the ‘decision’ (in consciousness) to act or not to act is itself the ‘result’ of preceding neural activity.” This argument is based on my own evidence that a period of up to 500 msec of cerebral activity is required to produce a conscious sensory experience (Libet 1993, for review).But conscious control of a process is not the same as becoming aware of the volitional intent (Libet 1985, 563–564). Control implies the imposing of a change, in this case after the appearance of the awareness of intention to act. Conscious control may not necessarily require the same neural “time-on” feature that precedes the appearance of awareness per se. There is presently [End Page 95] no directly applicable evidence against the appearance of a conscious control function without prior neural processes specific to its initiation.In short, one cannot cavalierly dismiss the possibility of a conscious free will function on the basis of a belief that such a control function must be itself initiated unconsciously by prior specific neural processes. The argument that conscious free will control is simply a useful delusion must still be regarded as a philosophical belief, not a scientifically demonstrated proposition.Spence goes on to suggest that “Consciousness is necessary for purposeful (intentional) action but it is not the initiator.” But if Spence is consistent in his view that all conscious functions are preceded by specific neural activities that initiate the function, then his putative role for consciousness would have been itself initiated unconsciously. How, then, would consciousness be “performing (purposeful, intentional) actions with subtlety and invention” if it is simply an after-effect of the responsible cerebral process? It would appear that Spence is postulating an active role for consciousness in directing the course of neural activities carrying out purposeful, intentional actions. That is the kind of potentiality I was suggesting must be kept open, but one that Spence dismissed elsewhere as “flawed.”On a technical point: The Grey Walter experiment is cited as evidence for postulated effects of timing, in the “illusion” of self-initiation of an act. However, that experimental result was simply due to the fact that the motor cortex initiates the command... (shrink)

An extended examination of Libet's works led to a comprehensive reinterpretation of his results. According to this reinterpretation, the Minimum Train Duration of electrical brain stimulation should be considered as the time needed to create a brain stimulus efficient for producing conscious sensation and not as a basis for inferring the latency for conscious sensation of peripheral origin. Latency for conscious sensation with brain stimulation may occurafterthe Minimum Train Duration. Backward masking with cortical stimuli suggests a 125-300 ms minimum value (...) for the latency for conscious sensation of threshold skin stimuli. Backward enhancement is not suitable for inferring this latency. For determining temporal relations between stimuli that correspond to subjects' reports, theendof cerebral Minimum Train Duration should be used as reference, rather than its onset. Results of coupling peripheral and cortical stimuli are explained by a latency after the cortical Minimum Train Duration, having roughly the same duration as the latency for supraliminal skin stimuli. Results of coupling peripheral stimuli and stimuli to medial lemniscus (LM) are explained by a shorter LM latency and/or a longer peripheral latency. This interpretation suggests a 230 ms minimum value for the latency for conscious sensation of somatosensory near-threshold stimuli. The backward referral hypothesis, as formulated by Libet, should not be retained. Long readiness potentials preceding spontaneous conscious or nonconscious movements suggest that both kinds of movement are nonconsciously initiated. The validity of Libet's measures of W and M moments (Libet et al., 1983a) is questionable due to problems involving latencies, training, and introspective distinction of W and M. Veto of intended actions may be initially nonconscious but dependent on conscious awareness. (shrink)

While other philosophers have pointed out that Libet's experiment is compatible with compatibilist free will and also with weak libertarian free will, this article argues that it is even compatible with strong libertarian free will (SLF), \ie a person's ability to initiate causal processes. Contrary to what Libet suggested, the actions in the experiment were motivated by urges. It is in accordance with SLF that the urges had preceding unconcious causes. Furthermore, Libet's observation that vetoing is possible confirmes (...) SLF. (shrink)

With certain topics the general reader experiences a double-whammy wherein one must peer through a curtain of needlessly obscure jargon to try glimpsing something that is inherently weird in nature. Bell’s nonlocality was once such a topic, but authors have had considerable success over the years in showing where the line is between the enigma itself and the human-made oddities surrounding it . Libet-ology has yet to undergo that de-mystifying process. Accordingly, our first order of business here is to restate (...) its basic tenets in plain English so that only nature’s inherent puzzle is left on the table, free of certain peculiarities of the existing technical literature. We also address the question of the central topic versus its byways, as alluded to by ‘left turn into veto-as-volition’ in our title. In the ensuing parts of the paper, we look outside the field to see how hypnotherapy and Hinduism might shed light on it. (shrink)

Susan Pockett presents sound arguments supporting her reinterpretations of data that Libet and co-workers used to support a number of intriguing and influential conclusions regarding the microgenesis and timing of conscious sensory experience and volitionally controlled motor responses. The following analysis, extending and elaborating some of her main arguments, proposes that Libet's experimental methodologies and rationales, and thus also his interpretation of data, are flawed and that neglect or ignorance of methodological and empirical constraints well known to sensory psychologists risks (...) drawing premature or faulty conclusions about the timing of conscious experience. (shrink)

In 1979, neuroscientists Libet, Wright, Feinstein and Pearl introduced the “delay-and-antedating” hypothesis/paradox based on the results of an on-going series of experiments dating back to 1964 that measured the neural adequacy [brain wave activity] of “conscious sensory experience”. What is fascinating about the results of this experiment is the implication, especially when considered in the light of Merleau-Ponty’s notions of “intentionality” and the “pre-reflective life of human motility”, that the body, and hence not solely the mind, is a thinking (...) thing. The experiments and conclusions of Libet et al. have attracted considerable academic attention and have been used in the development of psychological theories on automotivism and the adaptive unconscious. Moreover, they have engendered a series of important considerations in respect of the question of free will. This paper outlines the connections between the findings of Libet et al. and Merleau-Ponty’s ontology as presented in the Phenomenology of Perception. It is not our intention to argue that the former amounts to new wine in old bottles, but rather to show counterfactually that Merleau-Ponty’s ontology provides a theoretical framework which explains the experimental data obtained by Libet et al., and provides further speculative confirmation of the work stemming from neuro-physical research and emerging theories on the adaptive unconscious. (shrink)

In the 1980s, physiologist Benjamin Libet conducted a series of ex-periments to test whether the will is free. Whilst he originally assumed that the will functions like an immaterial initiator of cerebral processes culminating in actions, he later began to think that it rather works like an immaterial veto inhib-iting unwanted actions by preventing unconsciously initiated cerebral processes from unfolding. Libet’s veto was widely criticized for its Cartesian dualist and interactionist implications. However, in 2016, Schultze-Kraft et al. adopted (...) class='Hi'>Libet’s idea of an action-inhibiting veto and conducted a new experiment. Its goal was to test until which moment agents can inhibit an action that they already intended to do. Despite insisting on the material nature of the veto, the researchers also described the function of the veto in interactionist terms, namely as an act of the agent performed against her own cerebral processes. The purpose of this pa-per is to explain in which sense the veto in Libet’s and in Schultze-Kraft’s study is interactionist, and to provide a non-interactionist reinterpretation of the test subjects’ action inhibition in Schultze-Kraft’s experiment. (shrink)

Among Benjamin Libet's experiments on the relationship between consciousness and neural activity, those pointing at a substantive difference between subjective timing of a sensory experience and the experimental measure of the time needed to produce that experience appear particularly interesting. From a subjective standpoint, one is immediately conscious of a sensory experience, whereas, as a result of objective measured time of reaction, unconscious neural activation in the presence of a sensory stimulus begins 500 msec before one being aware of the (...) stimulus. In order to compensate this discrepancy, Libet introduces the notion of antedating. However, there is no fully satisfactory answer to the question about the conditions of possibility for antedating. Therefore, the very notion of antedating is highly problematic, though not infertile: the paradoxes present in this conception foster a profound review of the meaning of our experience of time and of the relationships between objective and subjective time. (shrink)

Libet’s timing experiments have resulted in some strong and unsavoury claims about human agency. These range from the idea that conscious intentions are epiphenomenal to the idea that we all lack free will. In this paper, I propose a new type of response to the various sceptical conclusions about our agency occasioned by both Libet’s work and other experiments in this testing paradigm. Indeed, my argument extends to such conclusions drawn from fMRI-based prediction experiments. In what follows, I (...) will provide a brief description of these experiments, sketch arguments one may be tempted to draw on their basis, and argue that such arguments rely on a questionable premise: that experimental subjects have relevant proximal intentions. (shrink)

Determinist thought with its sui generis view on life, nature and being as a whole is a point of view that could be observed in many different cultures and beliefs. It was thanks to Greek thought that it ceased to be a cultural element and transformed into a systematic cosmology. Schools such as Leucippos, then Democritos and Stoa attempted to integrate the determinist philosophy into ontology and cosmology. In the course of time, physics and metaphysics-based determinism approaches were introduced, and (...) a wide spectrum has emerged from genetics to behaviorism, from culture to psychology, from atomism to divinity. Determinism, whether physical or metaphysical origin, ignores freedom of will and deny agency competence over human behavior. Due to this feature, it is opposed by ethical theories, legal philosophies and religions. When the arguments for determinism are possible to disprove logically and philosophically, this is not so easy when the claims base themselves on scientific base. As the logical consequence of this novel fact, it is important to question the epistemological value of scientific knowledge and critically analyze the data of experiments and clinical studies in terms of methodology when answering any hypothesis such as neuro-biological, neuro-psychological, or neuro-theological argumentations. On the other hand, it is necessary to reach alternative experiments on the same subject or to show that it is possible to interpret them in different ways, as in the example of the Libet experiment. The neurobiological determinism based on biological reductionism, emerged as the result of ignoring the ontological difference of the mind, equating the mind with the brain, or defining mentality as an epiphenomenon of the brain. The main divergence stems from the acceptance of materialist philosophy. Paradigms that reduce existence only to matter do not take the metaphysical possibilities into account. In this case, although the problems called qualia or subjective experience stand there unresolved, the claim is preserved. Although many new developments such as the discovery of the entropy law, the big bang theory, and quantum physics have shaken the materialist philosophy, modern science resists an epistemological revision. However, with the current epistemology, it does not seem possible to grasp both the universe and the being as a whole. This is the most important reason why every attempt to understand the nature and spiritual side of human beings fails despite numerous experiments on the brain. However, the human brain is an organ that seems sophisticated and its secrets cannot be easily solved. Since there is not enough information about the brain, there is not enough evidence to claim that the brain, and therefore the mind, are part of the deterministic universe. Increasing brain researches since the last quarter of the twentieth century has revealed that genes, neurons and particularly brain chemistry claim much greater role than expected in human behavior. These results have been instrumentalized by some researchers for a radical claim that free will is an illusion, while by others it has led to the acceptance of will as less important over actions than was thought. Both ideas adopted a model of biological determinism in which freedom of will was ignored. Hypotheses based on controversial interpretations of various experiments raised concerns about religious, moral, and legal responsibility. Although man cannot be thought of as a non-free being from the point of view of common sense, the smog screen over the truth would not be lifted unless the scientific data in question had a correct interpretation. At first glance, it seems unreasonable to discuss universal determinism in the quantum universe. Nevertheless, the claim that strong causality prevails in the material world, including consciousness, remains in place. Therefore, firstly criticizing determinism and then examining biological determinism will help to fix the conceptual framework. This article aims to explain why genetics and neurobiology, while acknowledging their importance in the realization of behavior, can’t completely abolish moral agency. Some hypotheses attribute consciousness and free will to the physico-shimic structure of the brain, the random activity of neurons, or the ability to automatically transform inputs into outputs with the advantage of genetic information. This is the most sensitive and important point of being human; it attacks free will. Paradoxically, while global civilization of our time promises infinite freedom to human beings the science of the same age tries to prove that it is not free. (shrink)

Libet's experiments, supported by a strict one-to-one identity thesis between brain events and mental events, have prompted the conclusion that physical events precede the mental events to which they correspond. We examine this claim and conclude that it is suspect for several reasons. First, there is a dual assumption that an intention is the kind of thing that causes an action and that can be accurately introspected. Second, there is a real problem with the method of timing the mental events (...) concerned given that Libet himself has found the reports of subjects to be unreliable in this regard. Third, there is a suspect assumption that there are such things as timable and locatable mental and brain events accompanying and causing human behaviour. For all these reasons we reject the claim that physical events are prior to and explain mental events. (shrink)

Benjamin Libet's celebrated experiments concerning freedom elicited numerous attempts of _philosophical_ repudiation. Ten years ago, however, Judy Trevena and Jeff Miller published a _technical_ objection; they claim to have detected a,,smearing artifact" in Libet's calculations. This rests on a misunderstanding of Libet's methodology. In my reconstruction of Libet's argument, he draws an abductive inference to the best explanation. Now, Trevena's and Miller's objection does indeed lead to alternative explanations of Libet's measurements. These alternatives are _ad hoc_ and extremely improbable. They (...) constitute worse explanations than the explanation offered by Libet. _German_ Benjamin Libets bahnbrechende Experimente zur Willensfreiheit aus den Achtziger Jahren des vorigen Jahrhunderts gehören längst zu den Klassikern der Experimentalkunst. Aus _philosophischer_ Perspektive sind sie oft kritisiert worden; unabhängig davon ist zu Beginn des neuen Jahrtausends ein _technischer_ Einwand gegen Libet prominent geworden, der von Freiheitsfreunden gerne zitiert wird. Er geht auf Judy Trevena und Jeff Miller zurück und besteht in dem Vorwurf, dass Libet mit seiner Berechnung der _gemittelten_ Bereitschaftspotential-Kurven die wahren Verhältnisse verschmiere und dabei aus mathematischen Gründen den Anstiegs-Zeitpunkt des Bereitschaftspotentials künstlich nach vorne verschiebe – das ist der Vorwurf des sog. Verschmierungsartefakts. Ich zeige, dass der Vorwurf nicht sticht. Er beruht auf einem Missverständnis der Schlussmethode Libets. Laut meiner wissenschaftstheoretischen Rekonstruktion zieht Libet weder deduktive noch induktive Schlüsse aus seinen Einzelbeobachtungen; er schließt abduktiv, d.h. er schließt auf die beste Erklärung seiner Einzelbeobachtungen. Wie eine genaue arithmetische Analyse zeigt, bieten die Alternativ-Erklärungen, unter denen sich das Verschmierungsartefakt bewahrheiten würde, schlechtere Erklärungen als Libets Erklärung – sie sind an den Haaren herbeigezogen und extrem unwahrscheinlich. (shrink)

Since Benjamin Libet’s famous experiments in 1979, the study of the will has become a focal point in the cognitive sciences. Just like Libet the scien-tists Daniel Wegner and Thalia Wheatley came to doubt that the will is causally efficacious. In their influential study I Spy from 1999, they created an experi-mental setup to show that agents erroneously experience their actions as caused by their thoughts. Instead, these actions are caused by unconscious neural pro-cesses; the agent’s ‘causal experience of (...) will’ is just an illusion. Both the scien-tific method and the conclusion drawn from the empirical results have already been criticized by philosophers. In this paper, I will analyze the action performed in I Spy and criticize more fundamentally the assumption of a ‘causal experience of will’. I will argue that the I Spy study does not show that the agent’s causal experience of will is illusory, because it does not show that there is a causal ex-perience of will. Against Wegner and Wheatley’s assumption, I will show that it is unlikely that the participants in I Spy experienced their conscious thoughts as causally efficacious for an action, that they did not perform at all. It is more likely, that they experienced their own bodily movement as causally efficacious for a cooperative action, that they did not perform solely by themselves. (shrink)

Libet's experiments, supported by a strict one-to-one identity thesis between brain events and mental events, have prompted the conclusion that physical events precede the mental events to which they correspond. We examine this claim and conclude that it is suspect for several reasons. First, there is a dual assumption that an intention is the kind of thing that causes an action and that can be accurately introspected. Second, there is a real problem with the method of timing the mental events (...) concerned given that Libet himself has found the reports of subjects to be unreliable in this regard. Third, there is a suspect assumption that there are such things as timable and locatable mental and brain events accompanying and causing human behaviour. For all these reasons we reject the claim that physical events are prior to and explain mental events. (shrink)

Mental timing studies may be influenced by powerful cognitive illusions that can produce an asymmetry in their rate of progress relative to neuronal timing studies. Both types of timing research are also governed by a temporal asymmetry, expressed by the fact that the direction of causation must follow time's arrow. Here we refresh our earlier suggestion that the temporal asymmetry offers promise as a means of timing mental activities. We update our earlier analysis of Libet's data within this framework. Then (...) we consider the surprises which often occur on those rare occasions when neural timing experiments parallel mental timing work exactly. Together, these surprises and asymmetries prescribe a relentlessly meticulous and fully transparent exposition of timing methods, terms, and concepts which shuns plausible narratives, even when buttressed by rigorous formal models, unless guided by apposite empirical evidence. (shrink)

It is sometimes suggested that if, whenever we act intentionally, we do, or try to do, what we are most strongly motivated to do at the time, then we are at the mercy of whatever desire happens to be strongest at the time. I have argued elsewhere that this is false (Mele 1987, ch. 5; 1992, ch. 4; 1995, ch. 3; 1996). This essay provides another route to that conclusion, but that is not my primary aim. The goal of this (...) paper is to display the bearing of some well-known experiments by physiologist Benjamin Libet on this issue. Philosophical discussion of these experiments has focused on Libet's claims about consciousness. The significance of these experiments for the topics of motivation and agential control also merits serious attention. (shrink)

A remarkable hypothesis has recently been advanced by Libet and promoted by Eccles which claims that there is standardly a backwards referral of conscious experiences in time, and that this constitutes empirical evidence for the failure of identity of brain states and mental states. Libet's neurophysiological data are critically examined and are found insufficient to support the hypothesis. Additionally, it is argued that even if there is a temporal displacement phenomenon to be explained, a neurophysiological explanation is most likely.

We report two experiments in which participants had to judge the time of occurrence of a stimulus relative to a clock. The experiments were based on the control condition used by Libet, Gleason, Wright, and Pearl [Libet, B., Gleason, C. A., Wright, E. W., & Pearl, D. K. . Time of conscious intention to act in relation to onset of cerebral activities : The unconscious initiation of a freely voluntary act. Brain 106, 623–642] to correct for any bias in the (...) estimation of the time at which an endogenous event, the conscious intention to perform a movement, occurred. Participants’ responses were affected systematically by the sensory modality of the stimulus and by the speed of the clock. Such findings demonstrate the variability in judging the time at which an exogenous event occurs and, by extension, suggest that such variability may also apply to the judging the time of occurrence of endogenous events. The reliability of participants’ estimations of when they formed the conscious intention to perform a movement in Libet et al.’s study is therefore questionable. (shrink)

After a lecture in Göteborg by the neuroscientist Benjamin Libet in 1993, the Göteborg-Post carried the headline, ‘Now it has been proven: we are all somewhat behind’. The paper was referring to Libet’s celebrated discovery that the neural precursors of some voluntary actions occur before the conscious awareness of the decision to act. In a series of experiments in the 1980s, Libet showed that in an experimental situation in which subjects were asked to perform a simple voluntary action – (...) raising a finger – these acts were preceded by a rise in electrical activity in the area of the brain responsible for the causation of action, called the ‘readiness potential’ (RP). But the striking discovery is that while the RP is activated 550 msec before the action, the subject’s awareness of their decision to act occurs only 150-200 msec before the action. The conclusion is drawn that the causes of our actions in our brains occur fractionally earlier than our conscious awareness of deciding to do them. Hence the frequent description of the result of Libet’s experiments, that we are ‘living in the past’. (shrink)

Some recent physiological data indicate that the “subjective timing” of experiences can be “automatically referred backwards in time” to represent a sequence of events even though the earlier portions of associated neurophysiological activity are themselves insufficient to elicit the experience of any sensation. The challenge, then, is to explain how subjects can experience what they do in the reported ways when, if one looked just at certain neurophysiological activity, it would seem that perhaps subjects should report their sensations differently. The (...) phenomenon has seemed sufficiently remarkable to the neurobiologist John Eccles to count as evidence for mind-body dualism. This dualistic interpretation has resulted in a spirited attack by P. S. Churchland on both the physiological research and the dualistic interpretation. Her attack resulted in an equally spirited defense of the research by the primary investigator, B. Libet, where he reaffirmed his more guarded interpretation that “the temporal discrepancy creates relative difficulties for identity theory, but that these are not insurmountable”. In turn, Churchland has defended her criticism of Libet's research so that, for her, Libet's hypothesis remains “infirm and unconfirmed”. (shrink)

We all seem to think that we do the acts we do because we consciously choose to do them. This commonsense view is thrown into dispute by Benjamin Libet's eyebrow-raising experiments, which seem to suggest that conscious will occurs not before but after the start of brain activity that produces physical action.

Libet's (2000) arguments in defense of his interpretation of his experimental results are insufficient. The claims of my critical review (Gomes, 2008) do not suffer with his new statements.

The concept of free will has been heavily debated in philosophy and the social sciences. Its alleged importance lies in its association with phenomena fundamental to our understandings of self, such as autonomy, freedom, self-control, agency, and moral responsibility. Consequently, when neuroscience research is interpreted as challenging or even invalidating this concept, a number of heated social and ethical debates surface. We undertook a content analysis of media coverage of Libet’s et al.’s :623–642, 1983) landmark study, which is frequently (...) interpreted as posing a serious challenge to the existence of free will. Media descriptions of Libet et al.’s experiment provided limited details about the original study. Overall, many media articles reported that Libet et al.’s experiments undermined the existence of free will, despite acknowledging that several methodological limitations had been identified in the literature. A propensity to attribute greater credibility than warranted to neurobiological explanations could be at stake. (shrink)

Benjamin Libet’s work paved the way for the neuroscientific study of free will. Other scientists have praised this research as groundbreaking. In philosophy, the reception has been more negative, often even dismissive. First, I will propose a diagnosis of this striking discrepancy. I will suggest that the experiments seem irrelevant, from the perspective of philosophy, due to the way in which they operationalize free will. In particular, I will argue that this operational definition does not capture free will properly (...) and that it is based on a false dichotomy between internal and external causes. However, I will also suggest that this problem could be overcome, as there are no obvious obstacles to an operationalization of free will that is in accord with the philosophical conception of free will. (shrink)

This article argues against Benjamin Libet's claim that his experiment has shown that our actions are caused by brain events which begin before we consciously undertake the action. It clarifies what exactly should be meant by saying that the readiness potential causes, initiates, or prepares an action. It shows why Libet's experiment does not support his claim and why the experiments by Herrmann et al. and by Trevena \& Miller provide evidence against it. The empirical evidence is compatible (...) with strong libertarian free will. Neither the readiness potential nor the lateralized readiness potential cause our actions. (shrink)

Alfred Mele develops a conceptual analysis of some of the concepts that inform the recent experimental studies of intentional action. Based on a distinction between unconscious urge and conscious decision, he suggests that the neural activity described by Libet’s experiments may represent an urge to move rather than a decision to do so, and that the decision to move might be made only when the subject becomes conscious of the urge. If this is the case, then Libet’s experiments (...) do not threaten freewill. (shrink)

Libet demonstrated that a substantial duration (>0.5-1.0 s) of direct electrical stimulation of the surface of a sensory cortex at a threshold or liminal current is required before a subject can experience a percept. Libet and his co-workers originally proposed that the result could be due either to spatial and temporal facilitation of the underlying neurons or additionally to a prolonged central processing time. However, over the next four decades, Libet chose to attribute the prolonged latency for evoking conscious experience (...) to a prolonged central processing time. In my view, Libet has not provided any convincing evidence, either on the basis of his own past work or in his critique of my paper, for his hypothesis of a central processing time exceeding 0.5s before conscious experience emerges following direct electrical threshold stimulation of the cortical surface. I stand by my original results and conclusion that such prolonged latencies are largely the consequence of a dynamically increasing cortical facilitatory process that begins hundreds of milliseconds before there is a sustained neuronal activation. In some cases, the facilitatory process must overcome an initial stimulus-induced inhibition before neuronal firing commences. (shrink)

Moral responsibility is centered on the idea that, given some conditions, people deserve blame or credit, punishment or reward. At least according to traditional readings, moral responsibility presupposes free will, understood as the ability to choose independently of previous events. The achievements of neuroscience in recent decades make a very good case for the hypothesis that the mind is a material entity, a subset of the electrochemical activity of the brain. However, if the mind is a material entity, then it (...) is subject to physical laws. According to some interpretations, this entails the affirmation of determinism and the denial of free will and moral responsibility. This article reviews some of those achievements and their likely impact on the attributions of moral responsibility. The first section presents evidence from lesion studies, imaging techniques and direct electrical stimulation of the brain and argues that the convergence of results from these methods supports the hypothesis that the mind is the activity of the brain. The next section concentrates on studies that are usually taken as directly threatening free will–Libet’s experiments and the apparent mental causation theory. The third section turns to the implications of these findings for moral responsibility, explaining determinism, epiphenomenalism, libertarianism, hard determinism and compatibilism. Finally, the last section defends that the requirement of free will as a precondition for moral responsibility should be replaced by the requirement of more naturalistic properties, such as behavioral flexibility, self-control and natural autonomy. (shrink)

Moral responsibility is centered on the idea that, given some conditions, people deserve blame or credit, punishment or reward. At least according to traditional readings, moral responsibility presupposes free will, understood as the ability to choose independently of previous events. The achievements of neuroscience in recent decades make a very good case for the hypothesis that the mind is a material entity, a subset of the electrochemical activity of the brain. However, if the mind is a material entity, then it (...) is subject to physical laws. According to some interpretations, this entails the affirmation of determinism and the denial of free will and moral responsibility. This article reviews some of those achievements and their likely impact on the attributions of moral responsibility. The first section presents evidence from lesion studies, imaging techniques and direct electrical stimulation of the brain and argues that the convergence of results from these methods supports the hypothesis that the mind is the activity of the brain. The next section concentrates on studies that are usually taken as directly threatening free will – Libet’s experiments and the apparent mental causation theory. The third section turns to the implications of these findings for moral responsibility, explaining determinism, epiphenomenalism, libertarianism, hard determinism and compatibilism. Finally, the last section defends that the requirement of free will as a precondition for moral responsibility should be replaced by the requirement of more naturalistic properties, such as behavioral flexibility, self-control and natural autonomy.Key words: moral responsibility, ethics, neuroscience, neuroethics, autonomy. (shrink)

Agent causation presupposes that actions are behaviors under the causal control of the agent’s mental states, its beliefs and desires. Here the idea of conscious causation in causal explanations of actions is examined, specifically, actions said to be the result of conscious efforts. Causal–functionalist theories of consciousness purport to be naturalistic accounts of the causal efficacy of consciousness. Flanagan argues that his causal–functionalist theory of consciousness satisfies naturalistic constraints on causation and that his causal efficacy thesis is compatible with results (...) of Libet’s experiments on conscious causation. First, the notions of conscious effort and conscious causation are analyzed with respect to the project of naturalizing the mind, that is, the attempt to assimilate folk-psychological explanation to the causal model of explanation in the natural sciences. It is argued that a serious obstacle for any naturalist program is that mental states are individuated by their semantic content, not the mechanistic, physical properties of their neural state instantiations. In particular, it is argued that explanation by reference to mental state content yields not a causal but an interpretive or rationalizing account of action in which the question of causal efficacy is irrelevant. Then, Flanagan’s causal–functionalist theory of consciousness is critically assessed; specifically his interpretations of Libet’s negative experimental results on the causal efficacy of consciousness are diagnosed and disputed. It is contended that Flanagan misinterprets the results of Libet’s consciousness experiments and that his functionalist concept of consciousness fails to yield an adequate explanation of the alleged causal efficacy of consciousness. Finally, his thesis is countered with other experimental results that appear to favor an epiphenomenalist view over the causal efficacy account of consciousness. (shrink)