In brief: The experiments do not refute freedom. They refute the applicability of the category of linear cause to spirit. And what they measure is something Hegel himself holds to be unfree: the groundless impulse he calls arbitrary will.
1. What is measured
In the Libet experiment and its successors a person is asked to raise an arm at some point and to note the moment of the conscious decision. What is measured is that a neuronal readiness potential precedes that moment. The finding is solid; the inference to unfreedom is not.
For what is measured here is an isolated impulse without a ground – „now“ rather than a moment later, with nothing depending on it. § 15 determines precisely this as arbitrary will and states expressly that it is not freedom:
When one hears it said that freedom in general consists in being able to do what one wants, such a notion can only be taken as a complete lack of intellectual cultivation … Arbitrariness, instead of being the will in its truth, is rather the will as contradiction.
Groundlines, § 15 note
Hegel and brain research agree at this point, then: the groundless impulse is no freedom. It is nature. The dispute begins only with the question whether there is anything besides it.
2. The category mistake
The second and more important objection concerns the form of the inference. The scientific understanding looks for causal chains: cause A produces effect B. Applied to a thing this is right. Applied to spirit it is inadequate, because spirit is not a thing caused by another thing but a relation that relates itself to itself.
In the Logic this transition has a definite place: causality is not the last determination there but passes over into reciprocal action – and this into the concept, that is, into what determines itself. Whoever takes causality for the highest available category has decided the question before measuring.
3. What self-determination looks like
Freedom is in Hegel no moment that could be measured but a relation with two sides.
Character. Action does not come out of nothing but out of what has been acquired through upbringing, cultivation and habit. § 151 calls this second nature:
the habituation of it as a second nature, which is put in the place of the first, merely natural will, and is the pervading soul, meaning, and actuality of its existence.
Groundlines, § 151
The distance. But spirit is not identical with this character. § 7 determines the free will as the capacity to determine itself and in doing so to remain „with itself“ – to know its own determinacy as its own and not to be bound by it. Translated: one’s own habit can be made an object and measured against a standard one thinks.
With that the linear chain collapses. The present decision, the formed character and the thought standard are not cause and effect one after another but moments of a relation in which each determines the other. Character is the result of earlier decisions; the present decision is character relating itself to a universal.
4. Two perspectives on the same thing
The two considerations do not contradict one another. From outside, natural science sees an extraordinarily complex organ that learns by feedback, organises itself and forms a second nature – the material existence. From inside, philosophy comprehends its structure and purpose. And the self-description of this self-organising relation is exactly what the Groundlines set out.
An analogy: a technician sees on a hard disk a determined sequence of magnetic charges and says it is nothing but that. The reader says it is Faust’s monologue. The technician is empirically right. But the truth of those charges is the monologue – it does not escape the physics of the disk; it is its meaning.
Freedom does not mean escaping
Freedom is in Hegel not the absence of determinacy but its highest form. Unfree is what is determined from outside – the stone that is pushed, the impulse that befalls one. Free is what determines itself.
For imputation something practical follows: responsibility does not mean that the deed was undetermined. It means that it follows from what someone is – and that he answers for it. That is exactly how present-day criminal law works; see Is Hegel’s theory of punishment still of use?
Sources. Groundlines § 4–§ 7 (the three moments of the will), § 15 and note (arbitrary will), § 21–§ 24, § 151 (second nature), § 132 (right of the subjective will). – Science of Logic II, third section (causality and reciprocal action); Encyclopaedia (1830) §§ 153–159. – On the experiments: Benjamin Libet et al., „Time of Conscious Intention to Act in Relation to Onset of Cerebral Activity“, Brain 106 (1983); on the philosophical criticism of the inference drawn from such findings compare the debate on the so-called category mistake of neurodeterminism. – In the glossary: Arbitrariness, The Will, The Syllogism.