The real world exists as much as human beings exist. However, only humans are capable of imagining the impossible and this is obviously not a deterministic property of a non-free entity. What do we mean by “imagining the impossible”? Let me perform a very simple mind experiment: in this exact moment I'm imagining an apple falling upwards, towards the sky: an impossible event in the real, deterministic world. Nevertheless a neuronal ensemble in my brain is producing the inverted falling of the apple!

I choose to imagine an apple falling upwards exactly as I choose to imagine more or less possible (or probable) circumstances, and indeed to imagine the consequences of these circumstances despite the fact that they may be impossible within a deterministic system. Independently of how the brain does it, non-deterministic imaginary circumstances can be produced without apparent limits.

Since free will is similar to choosing between imagined consequences, I agree with Perlovsky's approach, seeing the brain also as a 'predictive machine', the workings of which we are unable to explain in a deterministic way. Perlovsky challenges the premise of essential determinism in science. Determinism could in fact be considered more a method for science than an absolute characteristic of the real world. For example, the concepts of 'true' and 'false' are undergoing reconsideration in the light of new concepts of uncertainty and fuzzy logic. A free decision would seem impossible in a deterministic system, since such a decision would arise 'out of the blue' (it would not be the consequence of any known premises). However, it may not be necessary for us to imagine a free decision as a sort of mental Big Bang: as Perlovsky suggests, we can examine the possibility that free will does not belong to the category of classical logical systems.

What is to stop us from thinking of free will as a form of imagination? Free will, choice and imagining the impossible all share the capacity to violate the principles of determinism in a way which is obvious to all of us. If we were to admit that free will is simply a form of imagination concerned with imaginary predictions, the problem of free will would simply overlap with that of imagery and imagination. In other words, free will could be simply a particular form of human imagination,  and we all recognise that imagination does not function in a deterministic way from a phenomenological perspective.

It is also worth noting that particular types of imagery evolve over time to have an increasingly stable form linked to cultural sharing. Moreover, although scientists often use mental time as an instrument in their work, imagination is an aspect of mind-brain which is time-free: abstract thinking would have had to evolve free from significant time constraints, not embodied in a quick stimulus-response cycle (and therefore obviously in circumstances which did not represent any immediate danger).

I do not know whether we imagine that we have free will, just as we can imagine seeing an apple falling upwards. What we do know is that Galileo and Newton, for their purposes, chose to imagine and study objects which fell downwards.

To conclude, I believe that free will is a problem which seems increasingly Hard to us the more we regard it as being isolated from the other forms of imagination. Neuroscientists treat imagery as a scientific problem, so why not also free will, simply as one of the mechanisms of imagination?

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Dear Dr. Sara,

Your comment is excellent. Free imagination is an excellent example of free will. It demonstrates that Dr. Libet’s experiments and related discussions doubting existence of free will are fundamentally misguided.

But an idea that free will is an imagination is wrong. Free will actually exists and guides our actions.

My article on free will has three main points:

1)      Free will actually exists

2)      Philosophical difficulties about free will are misguided by an idea about the mind being a logical system, which is wrong. The difficulties belong to logic, not to the mind, and not to the correct understanding about brain-mind functioning

3)      Free will is a mental representation (like all other ideas; along with neural mechanisms, connecting our ideas to our behavior). Representation of free will has ancient biological roots extending back to Amniotes, and in some way even to more ancient mechanisms. A large part of human representation of free will has been developed in cultural evolution. The content of this representation actually affects our behavior.

Leonid Perlovsky

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I gather that one of the aims of Dr. Perlovsky's approach is to decouple thinking from the physical world. Readers would find it easier to follow the argument, I believe, if the term 'volition' were substituted sometimes for 'free will'. For example, in paragraph 1.1 (page 2 of the pdf), there are two sentence beginning with "If...." One concerns classical mechanics, the other QM, and both contain the term 'free will'. To my way of thinking, it would be more comfortable in that context to speak of 'volition' (a word that I used to think of as Philosophy Department jargon, but over time I'm starting to see its value). Here's how the rationale would work in this context: To get from the object level of physical laws (whether classic mechanical or quantum mechanical or some other exotic type) all the way up to the subjective level where humans (generally) have a sense (valid or invalid) of "free will" is a long tortuous route -- at least in the theoretical world that is pre-Perlovsky, so to speak, and dominated rather by Libet's followers. Given the great "distance" between physical and psychic events in that context, if one attachs the word 'volition' to the low-level physics stuff (If x, volition is impossible; if y, volition is still impossibe), the reader is already primed perhaps for the decoupling that comes eventually in the paper. And by the same token, it would smooth the way for the identification of free will as a "cultural achievement" in paragraphs 1.7 and 1.8 (= pages 4 & 6 of the pdf), where we are certainly NOT talking about bare bones 'volition' any more.

(Playing devil's advocate, one could argue that throwing the term 'volition' into the mix only confuses the reader with too many terms. True, but the topic is inherently messy -- we're not just pretending that it is, so I think making the 'volition'/'free will' distinction can be justified.)

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  Paper in OJPP, Feb 2012,  entitled "Recovering from Libet's Left Turn into Veto-as-Volition: A Proposal for dealing honestly with the central mystery of Libet (1983)"

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The imagined "apple falling upward" in Dr. Sara's comment (01 Mar 2012) reminded me of a page in Nick Herbert's Quantum Reality where he talks about rainbows (to help explain to his readers what Heisenberg meant when he once said "Atoms are not things"):

"An example of a phenomenon which is objective but not an object is the rainbow" (Herbert, p. 162, ital. added).

I.e., at the level of scientific monism, there is a physical rainbow representation in the brain, yet no rainbow object in nature that corresponds to that internal image. (So, thank you Dr. Sara for reminding me of that 1985 book!) I think this is important because a possible objection to Dr. Perlovsky's scheme, to the extent that I understand it, might go something like this:

"He proposes a way to free us from the stifling monism/dualism dilemma of the ages with a new theory of thinking that can coexist side by side with scientific monism. But if it walks like a dualist duck, and quacks like a dualist duck, then isn't it STILL some exotic form of dualism? I feel that I'm being tricked somehow. I worry about the stealth dualism that was discovered belatedly inside Libet's scheme, for example." [Hypothetical critic of Perlovsky's scheme].

But with Herbert's rainbow example to point to, I believe the kind of objection that I just sketched out (call it "duck dualism") could be countered, if it ever arose, by saying, "No, this is a truly different framework that we're working in, not just a clever end-run around the old one. There is no trick to worry about. In Nick Herbert..." Etc.

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  Recent paper on Libet in OJPP.

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