Mental Cause

In several essays on the broad subject of free will I have said that there are three types of causation in our physical universe: micro-physical indeterminism, macro-physical determinism, and agent-volition, the last subjectively experienced as the willful exercise of one’s mind’s causal capacity, “mental cause”. I refer to what Aristotle called “efficient cause”, that is the immediate forerunner (or forerunners) of a particular event or outcome taken to mean “that which physically brings that particular event about.” Aristotle defined four types of causes, three of which could be said, sometimes, to have “mental” aspects. A simple example here, a fire in a fire-place, will serve to illustrate Aristotle’s distinctions.

1. The “material cause” of the fire is that out of which it could be made. Wood or paper might work. Water would not. There also has to be some oxygen (or other oxidizer) present and so on.

2. “Formal cause” has to do not with the fire’s material substrate but its shape. Not all arrangements of even qualified materials will successfully light. To make a nice fire place fire, the wood and paper have to be arranged in certain ways. Many but not all possible arrangements will serve.

3. “Efficient cause” is that which physically brings the fire about. It might be a lit match set to paper for example. When physics talks about causes, it is this they are talking about. Importantly, there can be chains of efficient causes. To set my wood pile alight with a match I must first strike the match and light it, then hold its flame under my paper kindling. That last step is commonly called also the “proximate cause” and it is mostly this that this essay is about.

4. Aristotle’s fourth cause, the “final cause” is the reason we have built and lit our fire. We want to get warm. Notice that this cause is only indirectly connected to our fire. Besides starting a fire we might get warm in other ways. We could do physical exercise or put on a coat. The entire set up of the fire from the material (wood and paper), its arrangement, to its ignition, are merely means to this end.

Under normal circumstances, we would always attribute “final cause”, to a desire, aim, or objective (purposeful intention) of the agent to get warm. If “mental cause” (of any sort) even exists, final causes would always, by definition, be mental. “Material causes” (that wood and paper in the presence of oxygen can burn) are not typically thought of as mental. Formal causes (the arrangement of the wood and paper in the fire place) might or might not be mental. The wood and paper in their pre-light configuration is not mental per-se, but the arrangement-design might or might not be. In the case of our fire place an agent is involved, but for example in a natural forest (arrangement of trees) ignited by lightening, it is not. As with formal cause, efficient cause might or might not involve mentality. In the case of our fire place, an agent lights the fire, but in the forest fire, lightening does the job.

Notice that from a third-party viewpoint, efficient (causal) agency remains always a physical object. What lights our fire place is a body with arms and hands that strike matches, and so on. There is no need to assume mental cause is real from an outside perspective. When we get to an inside perspective however the situation is quite different.

WHY DO WE NEED MENTAL CAUSE

What we need is some justification for believing mental cause exists, that it belongs in our ontology and “is real” by virtue of being one of the causes (somewhere in the chain of efficient cause) of [some] physical event. When we observe what we take to be a minded agent (human or animal) we see that the physical effects they engender are always products of a body’s motion. No one disputes the physical connection between the body and the rest of the world. The issue comes down to “what moved the body”? The answer is muscles of course, nerves, and more nerves comprising some part of the brain. The question is, was there something that isn’t a nerve as such (though a nerve would be involved) but something quintessentially mental, perhaps a desire or something like that lying at the beginning of the chain of efficient-causes?

Most people would say that it “seems as though” this is the case. Physics says this seeming must be an illusion because it discovers only two kinds of causes in the universe, the indeterminate and the determinate. To be sure, discovered here means measured. Physics detects, with physical instruments, only two types of causes. Speculation about mental cause goes back as far as the earliest recorded philosophy, but physics has never been able to detect it!

If however there is no mental cause when we seem so strongly to sense that there is, all sorts of philosophical problems arise. Mental cause is not the same as free will, but free will entails mental cause. Physics of course denies free will is real But if I am not warranted in believing my agency can be a cause, at least of my own body’s motion, how am I warranted in believing anything? Belief itself (causal or not) is a quintessential mental phenomenon. If my causal capacity is an illusion why not also my agency, and why not anything I might happen to believe or desire?

We can be deluded about our beliefs being true, but it is difficult to believe we are deluded about having beliefs, and doubly so for desires. The debate isn’t usually about having (subjectively experiencing) beliefs, but rather about their being anything “over and above” brain states. If physics calls my very agency into question (not the illusion of it, but its being something more than brain states) what is it then that has beliefs and desires? Can “brains” be an answer? How do brains, qua brains, come to have beliefs and desires? Do the mechanisms of a clock know the time of day in the sense that a human knows it when she looks at the clock? To deny brain states beneath (the foundation) of our mental states would in this day be absurd. The issue is always ultimately the ontological status of what appears, the subjective, as a result of their presence, and what (if any) downward causal powers the appearance has.

These sorts of issues are but the tip of the iceberg. If mental cause (and so by extension free will) is an illusion then a radical skepticism about everything would seem to be warranted. At the same time, even skepticism, since we must be skeptical of our very agency, is not warranted either. There is a long literature here, but as John Searle put it (The Construction of Social Reality [1995]) nothing about the human experience nor all of human history makes any sense without presupposing free will.

WHY IS MENTAL “EFFICIENT CAUSE” CONTROVERSIAL?

I have given some answer to this above: because physics cannot measure it. It would seem unproblematic to take for granted that physics doesn’t cover everything; it is, as the matter is put, incomplete. But the problem is more subtle than that. The two types of causes that physics can measure (strictly speaking physics cannot measure quantum phenomena directly, but only when these interact with the macroscopic world) have qualities, characteristics, that mental causes lack. These qualities are what explain in the sense of “reveal the mechanism for” physical causation. There is no mathematics in physics, no observation or experiment that would suggest that anything other than prior-physics can be a cause in physics. Even not-directly-observable quantum phenomena are readily observed via these same qualities when they interact with the macroscopic world. Purportedly “mental causes”, by contrast, do not appear to share these qualities. As a result, they cannot be observed from a third party viewpoint, and so no path exists to an explanation of the mechanism of their effect on physics.

Rather than accepting that some mysterious sort of cause that cannot be observed must be real, physicists and most philosophers instead move to strike “mental cause” from the list of causal possibilities in our universe. This is a philosophical move, an induction based on evidence from the only sort of detection or measurement instruments, physical instruments, that exist. The anti-physicalist might respond by claiming that while physical instruments can not in principle measure mental cause, subjective consciousness, literally our phenomenal arena detects them, and this arena is, after all, also a part of the universe along with everything else.

At this point we are thrown back upon the brain which is indisputably physical. We know that the movement of my arm is preceded by nerve impulses in my arm and brain that are themselves indisputably physical. If at the top of this chain of efficient cause there was a mental event that set the chain in motion it behooves the proponent of mental cause to say how, that is by what mechanism, the mental event effects (that is trigger) the first indisputably physical (nerve) process in the chain?

CHARACTERISTICS OF MATERIAL and MENTAL CAUSES

According to Phil Dowe (Physical Causation [2000]) material cause is all about transferring some [physically] conserved quantity momentum, mass-energy, or electric charge. If one billiard ball strikes another momentum is transferred from one to the other. This results in two other observations important in this context. First physical cause is temporal. Causes precede their effects. The transfer of a conserved quantity cannot take place faster than the speed of light. Second, there is a reciprocal impact of the effect on the cause. If one billiard ball gains momentum, the other loses it.

Both of these qualities are absent from mental cause. In this context, distinctions made by Nicholas Rescher (“Free Will: A Philosophical Reappraisal” [2008]) will be helpful. Rescher is aware of the overall relation between consciousness (including mental cause) and brain states. He claims that there never can be any instance of mental cause without the simultaneous existence of some correlated brain state. If we look for a mental event that brings about a brain state, but isn’t itself associated simultaneously with some other brain state, we will never find it. “Mental causes”, in Rescher’s terms are not causes in Dowe’s physical sense.

Mental causes are not, in Rescher’s view, temporal. They are literally (metaphysically) simultaneous with their effect, some brain state. He distinguishes this sort of a temporal cause by calling it “initiation”. Initiation (often intentional but not necessarily so) need not evoke a neurological correlate ex nihilo. It need only slightly modify an existing state. From a third party viewpoint, that modified state would appear a perfectly natural evolution from its own prior state. Nothing would be found to suggest that anything non-physical was responsible for it.

This “a temporal initiation” is possible because in mental cause, no conserved quantity is transferred, and consequently there is no reciprocity. If I elect to pick up a rock and throw it at a window, I can feel the momentum transfer between my arm and the rock, and of course the throw is temporal. But the initiation of the event was simultaneous with the physical brain state that lies at the top of the physically [efficient] causal chain. The evidence that this is so is our experience that there is no reciprocal effect of my choice to initiate a rock-throw back on that initiator. Nothing about the initiation impacts back on the mental cause itself. Of course I may, this being a directed (intentional) initiation, immediately regret having done so. But that is a different, subsequent, thought, not a modification of the original one.

If Rescher is correct about initiation, how can we tell if the choice (mental cause) results (simultaneity being granted) in a correlated brain state or the other way around? We cannot tell based on any physical measurement. Physicalists would say there is no reason not to suppose that the physical is logically (if not temporally) prior. But if Rescher is correct, what then of the mechanism problem?

With regard to mechanism, many speculations seem to orbit about some interaction at the quantum level. The a temporal nature of initiation coupled with a lack of conserved quantity transfer and so lack of reciprocity, are suggestive of quantum entanglement where, on some views (see Ruth Kastner “Understanding our Unseen Reality” [2015]), the same qualities (or lack of them) characterize quantum phenomena. Since we cannot measure quantum phenomena directly, as far as we know, prior to some manifestation in the macro world (the exchange of a conserved quantity) the same qualities as characterize “mental cause” (initiation) might characterize “quantum cause”. The most detailed speculation with regard to mind might be Henry Stapp’s (“Quantum Theory and Free Will [2017]) Quantum Zeno Effect (QZE), mind’s ability to hold or otherwise modify subtle quantum indeterminacy within the anatomical and physiological processes of the brain. True, even QZE does not say exactly how this power of the mental connects up to the physical, but in this case, neither side of the transaction can be directly measured and there are reasons to believe (see the aforementioned Kastner book) that quantum phenomena are also initiations in Rescher’s sense.

WHAT IS MENTAL CAUSE

Above I have looked at mental cause from the physical side. What does it look like from the mental side? Some philosophers have characterized mental cause in terms of beliefs or desires. But beliefs and desires are not mental causes in Aristotle’s efficient sense. They are Aristotelian “final causes” and clearly mental, but not our issue here.  Being a reason is of course mental, but not all of what is mental is also causal. I might want to get warm (my reason for lighting a fire) but not move a muscle to do anything about it. The quintessential efficient mental cause is a volitional act, an exercise of will on the part of a minded agent. In our experience, only mind, the subjective consciousness of an individual, has this ability to act volitionally, for a purpose, and not either indeterminate or determined by prior physics.

Purposeful cause is mental and only mental, and it is causal, that is itself determining of subsequent physics, for example my throwing a rock. As much as I disagree with Schopenhauer, I do believe he was correct in locating will and representation at the core of phenomenal experience, or as we would put these in more modern terms, intention and qualia. Mental cause, in particular our capacity to control intent and by extension a body, is an intrinsic component of our “what is it like to be…” experience.

Qualia are the mental effects of physical (brains) causes (an over simplification but for purposes of this essay I leave it at that, see “From What Comes Mind”). Intention is a mental cause (initiation) of a physical effect. Throwing a rock begins with an intention, but this is also true for subjective states that exhibit no gross physical effects. Suppose on a nature walk you come upon a beautiful flower. You attend to it, visually, perhaps also aromatically at the same time. Suddenly you become aware of a buzzing sound from behind or above your head somewhere. You cannot see what is causing the sound, but without moving your gaze from the flower you have become aware of it. Becoming aware is clearly a mental event which in this case may be comfortably attributed to prior physics (brain states, bearing in mind Rescher’s initiation can work in both directions). Only subsequently do we volitionally attend to the sound, perhaps to identify it. The volitional element entails agent purposeful-direction and so mental cause even if no muscle has moved.

Under normal circumstances, when we are conscious, we are never without both qualia and intention about something. Is it possible one can be conscious without intention, qualia, or both? Advanced Buddhist monks, masters at meditation, claim to achieve the first, but even this being so, they maintain this special state only while meditating. Sensory deprivation might suggest the possibility of a qualia-free consciousness, but people report made-up qualia, images and sounds brains generate (and to which we attend as we do in a dream state) in the absence of external stimulation. Perhaps we cannot be conscious in the absence of qualia.

MENTAL CAUSE AND FREE WILL

Mental cause is necessary but not sufficient for free will. In addition, free will demands agency, a subject whose will it is. An exercise of free willed choice is a volitional act of an agent. It is not either prior-determined, though often influenced, by physics, nor random. It is mental cause directed by agent-purposeful volition, itself quintessentially mental and unique to minded-agency in the universe. To get free will, mental cause must be real, and also subjective agency. The action of the body-agent of a physical event (throwing the rock) is willful only by extension from the [presumptive] mental-agent who is the initiator of that act. A body can sometimes act in the absence of agent consciousness. Such acts are not willful, and typically we do not claim that they are.

The connection between intention (willfulness) and subjective agency is built-in to human language. To speak of intention always implies subjective agency. So free will and mental cause are doubly linked. Free will rests on mental cause, but if free will is not real, there is nothing interesting left for mental cause to do. It is possible there are, for example, subconscious mental causes of which we are not aware (conscious of) and so not willed as such. But if in fact free will (not to mention agency as such) can be subsumed by brain states, there is no reason why subconscious mental cause could not be also.

An exercise of will (volition) by an agent is the quintessential “mental cause”. If free will is an illusion it is hard to understand the point of working to save mental cause. If all of our choices, our behaviors (including purely subjective sorts like “attending to”), are prior-determined by our brains what is left for mental cause to do? When Sean Carroll denies the possibility of free will because “If free will were real it would mean that mind causes physics” (The Big Picture [2016]) he is aiming, really, at mental cause. Free will goes along for the ride because it is the volitional exercise of the causal potential of mind that matters.

Agent volition then, and not beliefs or desires, is the epitome of mental cause. But if volition itself is prior-determined by brain states, and not a non-material (mental) agent, then there is no point to mental cause, the brain can do it all. In turn, mental cause, apart from the free will issue, is usually defended (or challenged) with reference to free will. The possibility of free will is grounded on the reality of mental cause and in addition the reality of the volitional agent able to utilize it. Both of these, in turn, rest on the reality of mind with the “power to cause physics”.

Adventures In Quantumland by Ruth Kastner: commentary and review

Picture of me blowing smoke

Ruth Kastner has made another effort to explain the “transactional theory of quantum mechanics”. My Amazon review of this excellent book is included below with a link to her text. In this commentary I address one technical aspect (or consequence) of the theory and separately her more speculative ideas in chapters 6 and 7 (both mentioned in the review). Her first attempt at explaining her ideas to a lay readership, the book “Understanding our Unseen Reality” 2015 is reviewed here.

The technical issue is I hope straight forward. In Dr. Kastner’s scheme, energy is not transferred, nor a spacetime event realized until a virtual or “incipient transaction” becomes a “real transaction”. Incipient transactions happen between any potential emitter of some quantum of energy, and all the possible absorbers of that quantum (the atoms that could absorb it) throughout the universe! They happen outside of spacetime and so their instantaneous virtual interaction throughout the universe is not at issue here.

What is at issue is that as I read her, no real transaction can begin until one of the emitter (offer wave) absorber (confirmation wave) pairs is promoted to a real transaction. A photon cannot be emitted until it has a determinate absorber destination! How does this idea work if the absorber is an atom in the detector of a telescope on Earth, and the emitter is a star in a galaxy 10 billion light years distant? How could there have been an actualized transaction between a star and a telescope that did not exist when the photon was emitted? I have identified two separate problems here.

First, the confirmation waves come from absorbers capable of absorbing the photon which, at the time of its emission, might have been an X-ray photon. But by the time of its real absorption by some atom in our telescope detector has been stretched way into the red end of the spectrum. It is possible that our red-capable absorbing atom could not possibly have produced a confirmation wave for an X-ray photon.

Secondly, at the time of the emission, the atom that ended up in the detector of the telescope might have been anywhere in the vicinity of the Earth/Sun system such as it was at the time, perhaps a just coalescing mass of hydrogen gas and dust swirling around a proto-star. How did that lucky atom end up in our telescope and not in the center of the Earth, or the moon or anywhere else in the solar system? Further the spatial relation between the proto solar system and our emitting star would be completely different than it is now 10 billion years later. But when we trace the path of our captured photon it always appears to have made a beeline (least time) path between the emitting star and that particular place in space where the Earth (and our telescope) just happen to be 10 billion years after emission.

I suspect Dr. Kastner has an answer here, or I am misunderstanding something about what she means about emission requiring an actualization between offer and confirmation waves. I hope she will address a query sent to her. If she does I will update this blog entry with her explanation.

In her chapters 6 and 7 she goes off the rails speculatively speaking. Her aim in chapter 6 is free will. There is nothing here that hasn’t been said before by others (broadly a theory called dual-aspect monism, see my “Fantasy Physics and the Genesis of Mind”). Kastner begins by demolishing the anti-free-will arguments of David Dawkins and others of a similar type. She does a marvelous job from the viewpoint of the idea’s epistemological absurdity. If there is no free will, then Dawkins’ book isn’t really “his” and so on. In this she is entirely right even to pointing out that the view reduces us to automatons, something I have said for years (see my “Arguing with Automatons”).

Kastner points out that if nothing else, quantum mechanics shows the universe is not fully deterministic. Quantum mechanics “makes room” for free will. That’s fair enough. She also recognizes that “making room” and “the phenomenon” (free will) itself are two different things. Why? Because free will is not merely not-determined (indeterminate) but purposeful. Free will introduces teleology and if not for the universe as a whole then at least for the free-willed individual. Choice is always exercised “for a purpose”, and this is something quantum mechanics doesn’t address unless…

Kastner’s next move, the metaphysical move, is where she goes wrong. Perhaps, she says, quantum phenomena are not merely indeterminate. Perhaps they are also proto-volitional; there is in the phenomenon that which leads directly to the human sort of free will through some ascending volitional hierarchy? Something is “built into physics” that bears the germ of volition. She is, in effect, saying: we have a mystery here (free will) and we have a mystery there (Quantumland), perhaps one mystery is the explanation of the other? Now she emphasizes that this move is pure speculation but what is the point of it other than to fix a source of volition in a universe that is otherwise determinate and indeterminate at the same time, but not volitional.

No one (including Dr. Kastner) asserts that virtual quanta are conscious, but nor can anyone (including Dr. Kastner) tell us in what exactly, besides the non-teleological behavior described so well by mathematics, this proto-volitional consists! What is even a single “identity characteristic” of a proto-volition? In what way does (or even might) proto-volition contribute to quantum measurement outcomes? Where would a proto-volitional term fit into the equations of quantum mechanics? If there is no place for it why say it (volition) might be there other than the purely metaphysical need to have it start somewhere coupled with the metaphysical assumption that there is nothing more to the universe than the physical (including Quantumland).

To put the matter another way, Quantumland is speculation but not “empty speculation”. There are observables, particles communicating at seeming space-like distances and being in two places at once. A “foundation to macrophysics” outside of spacetime makes perfect sense in this context. Raw space and time can be seen to emerge from its seething processes. Quantumland explains a lot. It gives us part of the mechanism of spacetime emergence, and it removes the mystery from many of its emerging observables.

By contrast there is no observable that demands volition at the microscopic level. That volition (or proto-volition) is to be located there explains nothing about the mechanism of [much later] emerging consciousness. Free will is expressed only by or through consciousness (human or animal) as far as we know. The speculation here is empty of content. Nothing stands as an example of a property that ultimately adds up to consciousness or the volitional will of consciousness.

Quantum mysteries are encountered at just the point where they enter spacetime, but volition is not encountered in any obvious way until we reach all the way up to macroscopic brains. This is not to say that quantum phenomena are not involved in producing consciousness. It would surprise me if they weren’t! But this does not mean that quantum phenomena are themselves volitional or even proto-volitional there remains no teleology in physics.

This then brings me to chapter 7 where there is a related problem. The problem in chapter 6 is the emptiness of the speculation, the ad hoc quality of throwing volition into Quantumland because materialism has no other place to put it. In chapter 7 the problem is an induction fallacy. That Eastern metaphysics refers to a world beneath (or above or beyond) that of our physical senses, a world that is the source of the physical, does not mean they are talking about Quantumland! A Buddhist or Hindu using the word ‘energy’ and a physicist using the same word are not necessarily talking about the same thing (Dr. Jacob Needleman pointed this out to me a long time ago using “The Tao of Physics” [Capra], one of the books Kastner mentions in this chapter). Of course they could be talking about the same thing, and if you read enough of both you can cherry pick qualities from each that seem to overlap. Kastner does this in this chapter.

At the same time, Dr. Kastner gives herself the clue to their difference. The “spiritual traditions” all ascribe some sacredness to that which underlies our ordinary reality, but she doesn’t fully grasp the implications. Sacredness is intrinsically teleological. The source of our ordinary reality according to the “spiritual traditions” is purposeful, and being indirect products of it, we human beings have some relation, some responsibility to that purpose. But in no wise does it make sense to say we have any responsibility to Quantumland (nor does Dr. Kastner say such a thing), and this is precisely because Quantumland is not teleological.

Kastner must realize this implicitly as she reminds us multiple times that her ascription of volition to Quantumland (chapter 6) has no bearing on her physical theory as such. But nor is the traditional ascription of sacredness to “the other” some sort of mistake on the part of such traditions. It is a necessary quality of the other to which the traditions refer; a demonstration (as it were) that they are not speaking of Quantumland! There is nothing wrong with calling attention to the fact that spiritual traditions refer to “another reality” underlying our ordinary experience. Quantumland is also another possible reality underlying the macrophysical. But they are two different kinds of “other reality”.

If materialists wish to insist that the sacred sort of other doesn’t really exist, I can only say that until such time as there are observables that pick one theory out over another the same can be said of all the competing quantum others advocated by physicists and philosophers today.

I will leave things here because after all neither of these chapters bears in any way on the transaction interpretation of quantum mechanics as a physical theory. Unlike in her addenda to this latest book, Dr. Kastner isn’t resolving any paradoxes in these chapters. Indeed the misapplied logic (chapters 6 & 7) and misunderstood metaphor (chapter 7) is all on her side; though again and to repeat, none of this has ought to do with the explanatory value of the physical theory.

Adventures in Quantumland: Exploring Our Unseen Reality. Ruth Kastner 2019.

In (2015) Ruth Kastner, a physicist and philosopher, published “Understanding Our Unseen Reality”, a layman’s version of her earlier “The Transactional Interpretation of Quantum Mechanics” (2014). This book, “Exploring Our Unseen Reality”, is something of an addendum to that earlier work. It is really two books in one. The first half (roughly) is the book, while the last half is a collection of papers authored by Kastner, and sometimes collaborators, each addressing a specific (usually in more technical terms) issue covered in the book’s first half. Kastner frequently refers back (by chapter and page) to her earlier book. It isn’t necessary to have read the earlier book, Kastner makes her overall case perfectly well in this book alone using minimally more technical language (really symbols) to which she introduces us. On the one hand, this book’s explication of the theory’s main points and implications is brief. On the other hand, Dr. Kastner has had a lot of practice explaining the transactional interpretation and this latest attempt is clear and succinctly expressed.

Beginning with the basics Kastner moves us through subjects that are important to understanding her with a particular emphasis on the fact that her theory does not demand (I get the impression she encounters this idea a lot) that some mind be present to “collapse the quantum wave function”. To be clear, there are wave functions that minds do collapse. the ones that end in a quanta-absorbing event in one of our sensory neurons (and from there up the chain to our brains). In general, however, wave collapse is the result, the completion, of a measurement and that means a transaction between a quantum emitter and some absorber whether that absorber is in an eye, a brain, or the detector of some instrument.

The key to the theory is that the transfer of a quantum (measurable energy) requires an interaction between an emitter and absorber. There are two sorts of interactions here, incipient and actual. Incipient interactions happen between an emitter (an “offer wave”) and every potential absorber in the universe (“confirmation waves”), literally every atom that can absorb a photon of that particular energy. It doesn’t matter if these potential absorbers are near to or far from the potential emitter (in the incipient stage nothing has been yet emitted). Every incipient potential occurs instantly and simultaneously throughout the universe. One of these “offer wave/confirmation wave” (confirming that some emitter is ready to emit) “incipient transactions” wins out (remember this has taken place in zero time and across all space from our viewpoint in timespace) and becomes an “actual transaction”. The photon is emitted generating the beginning of a real singular timespace event propagating at the speed of light, and ends when the winning absorber receives the photon. The absorption constitutes a measurement because energy is transferred between the emitting and absorbing atoms. The transaction is complete.

If Dr. Kastner is right here, her theory has implications as revolutionary as the original insight (energy is quantized) resulting in the first generation of quantum mechanics. It would mean that no real photon can leave an emitter until a real absorber is selected out of the incipient possibilities. Personally I do not see how this can be. What if the absorber, the one that completes the transaction, is at the business end of a telescope while the [real not incipient] absorbed photon was emitted from a star 10 billion light years away; long before that telescope existed? There are several potential issues here and I suspect Kastner has an answer, but she does not explicitly address this. See my blog for further discussion.

In the final chapters of the book Kastner gets speculative about quantum mechanics and mind or more specifically the possibility of free will. This is not the “mind collapses the wave function” business, but its opposite. Not only does quantum mechanics give us an escape from absolute macroscopic determinism (fair enough) but rather that the quantum realm is somehow proto-volitional. The last chapter explores some speculations on the potential analogy between Kastner’s Quantumland (beneath spacetime) and various ideas present in ancient Greek and Eastern (Hindu and Buddhist) metaphysics. Kastner follows others, citing references, in all of these speculations. I have problems with both of these ideas, but this is not for a review and Kastner is sedulous about these being purely speculative, having no direct bearing on the transactional theory as such.

Following her last chapter, Kastner gives us an epilogue calling attention to (and thanking) her predecessors in the explanatory thread leading to the transactional interpretation, followed by an addendum in which she addresses several long standing “quantum paradoxes”. Her aim here is to show that they are not paradoxes at all, but bad interpretations of data even apart from the transactional theory, and that the transaction idea can make paradox resolution easier to grasp.

In summary an excellent if abbreviated explication of the “transaction theory”. In response to her previous book I said that Dr. Kastner’s theory is the only one I’ve ever encountered that “explains quantum mysteries without explaining them away”. Having read this book I see no reason to change my mind.