According to both ID and OD, the physical and non-physical can interact. OD differs from ID by adding that God mediates between mental agents and their bodies. Although this sounds far-fetched, it gives OD an advantage over ID, for ID claims that the mental and physical are totally different, yet offers no explanation for how the mental and physical can interact. For a person who believes in God, and who believes that God performs miracles, OD is much more intellectually satisfying than ID. Furthermore, ID makes more sense if God exists than if God does not exist. This is because a sharp distinction between the mental and the physical is better accounted for by a supernatural cause than by any natural cause. Since it is likely that God exists if ID is true, the added claim of OD is not so far-fetched in this context. For the person who is liable to entertain either theory with a full understanding of each one, OD leaves fewer questions unanswered. Therefore, OD is a better theory than ID.
According to Descartes, God is "a supremely perfect being." (Stewart, pp. 73-4) As such, He is omnipotent, omniscient, and omnibenevolent. According to Christianity, God is good and God is love. If God is as good as Christianity teaches that He is, then it is difficult to believe that He would create puppets that feel as though they are self-determining agents. Insofar as they felt themselves to be self-determining, they would feel as though they have dignity, but since they are puppets, they would actually have none. Thus, God would be playing a cruel joke on the human race if PD is true. Since a good God would not play such a cruel joke, OD makes more sense than PD does, for human dignity is real under OD.
The first two mentalist theories that I want to compare are OM and SM. OM is the theory held by Bishop Berkeley. According to Berkeley, everything we sense is what it is because that is what it is in the mind of God. Our senses do not refer to anything outside any mind, but our observations agree with the observations of others because they are given to us by the same mind.
SM differs from OM by holding that there is no ideal observer who makes everyone else's observations agree. This would seem to be a serious flaw for SM, for the world does seem the same to different people, and something has to account for that. Since M holds that there is no external world, the only way it has left to explain objectivity is to say that something is so because someone says so. God does this job very well, but SM has no final authority to turn to. Thus, it seems that OM is better than SM. Nevertheless, there is a good reason for not making this decision just yet: SM is popular among some quantum physicists who say that quantum physics proves SM.
"The doctrine that the world is made up of objects whose existence is independent of human consciousness turns out to be in conflict with quantum mechanics and with facts established by experiments."(131)He also quotes N. David Mermin of Cornell as claiming that "`We now know that the moon is demonstrably not there when nobody looks.'"(131) These scientists believe SM not so much because of philosophical considerations, but because they believe it is the only world view consistent with Bell's Theorem.
Bell's theorem came about in an effort to resolve a debate between Niels Bohr and Albert Einstein. Their debate centered around Heisenberg's uncertainty principle, and on whether God played with dice, as Einstein put it. The uncertainty principle is the claim that there is an inverse ratio between our ability to determine a sub-atomic particle's position and momentum. Insofar as we can pinpoint its position, we cannot pinpoint its momentum, and vice versa. Bohr believed this was because sub-atomic particles were not really particles at all, but instead something that did not really possess position and momentum. So, he believed that Heisenberg's principle reflected a metaphysical fact. Einstein, however, believed that the uncertainty principle represented only an epistemological hurdle. He believed that there were hidden variables, and that we could measure both the position and momentum of a particle once we could detect the hidden variables. Einstein also believed that hidden variables would account for the seeming indeterminacy that experiments found in sub-atomic events. Bohr, however, believed that indeterminacy was a part of nature.
In 1964, John Bell of Lawrence Livermore Laboratory "showed that the experimental consequences of a local hidden variables theory such as Einstein's differ significantly from those of quantum mechanics." (Schick, p. 134) Subsequent experiments overwhelmingly supported quantum mechanics. An example of such an experiment measures the spin of sub-atomic particles. Whenever two spin ½ particles have interacted, they always have opposite spins. One has a ½ spin, and the other has a -½ spin. Experiments showed that whenever an experimenter reversed the spin of one such particle, its partner reversed its spin instantaneously.
According to Einstein's world view, however, such results are impossible. For Einstein, the universe consists of separate particles of matter that interact with each other by sending signals or by physically contacting each other. Signals, moreover, can go no faster than the speed of light, for any signal would consist in the movement of a particle with a positive mass, and according to relativity nothing can accelerate to speeds faster than light without using more energy than is contained in the entire universe. Therefore, it would be impossible for information to instantaneously travel from one particle to another.
According to Schick,
Bernard d'Espagnat argues that there are three fundamental assumptions at work in the Bell experiment. One is the notion that there is an external world that exists independently of our consciousness. The second is that we can use induction to discover truths about the world. The third is that nothing can travel faster than the speed of light. (p.135)D'Espagnat believes that experiments like the above indicate that one of these assumptions must go. The easiest one to let go, he believes, is the first, that an external world exists independently of our consciousness.[1] If we gave up the second, we would have to give up science, and if we gave up the third, we would have to abandon Einstein's theory of relativity. D'Espagnat is less prepared to give up science and relativity than he is to give up an external world. Therefore, he adopts SM.
Apparently, it has not occurred to D'Espagnat that he would have to give up physics if he stopped believing that anything is physical. After all, the first assumption, the one that he chooses to abandon, is that the world is physical. Also, he does not realize that the second two assumptions depend upon the first one. If the world has no objective existence outside anybody's mind, there can be no truths to discover about it. And if nothing is physical, nothing can travel at any speed whatsoever, for nothing can travel at all. Without a physical world, there is no sense in which we can distinguish here from there-- except as different ideas in someone's mind. Since the second two assumptions depend upon the first, it would be more reasonable to toss one of them aside.
Before I state his alternatives, however, I want to make one point. Instantaneous communication is no threat to the belief that nothing can travel faster than the speed of light, not even the perceived threat that Schick makes it out to be. In order for instantaneous communication to occur, it must occur by some means other than the travel of a signal. This is because no matter how fast a signal travels, whether it exceeds the speed of light or not, it will always take some amount of time. Therefore, any communication that occurs through signals will not be instantaneous. So, actually, the results of the spin measurement experiments give us no ground for rejecting locality, the belief that nothing can travel faster than light. Therefore, we do not really have to give up relativity if we give up the belief that instantaneous communication is impossible. Rather, we would have to give up the belief that all communication occurs by means of signals.
Nevertheless, we would have to give up part of relativity, namely the belief that causation is limited by the speed of light. Without this belief, we cannot say that space and time are one, and we cannot say that past and future are local to any point in space/time. Since these are the weirdest parts of relativity, however, they might be the easiest to give up. Still, instantaneous communication, and therefore instantaneous causation, is a strange idea, and we might find it too hard to accept. Let's look, now, at Schick's alternatives.
One alternative, he says, "is to give up the view that space and time are real."(p.136) This alternative amounts to Kant's Transcendental Idealism. Kant believed that there was a real world, but that it was unknowable. He believed that space and time and other synthetic a priori categories were mental constructs which we needed in order to make sense of the universe, but that it was ultimately wrong to describe the world in terms of these categories. By this view, then, we impose the concepts of space and time upon the universe, but they do not really apply to it.
Another alterative consists in "giving up the belief that the world is composed of a multitude of separate objects."(p.137) This is the view of David Bohm and the ancient Greek philosopher Parmenides. Parmenides argued that there can be no void because there can be no place where nothing exists. According to this view, the two particles are not separate objects. So when one is affected, it is only natural that the "other" is too.
A third alternative allows for the world to be made up of multiple entities by claiming that each always has full knowledge of the others. This is the view that the universe is like a hologram. According to Schick, this view "is known as `panpsychism' or `pluralistic idealism.'"(p.139) It is indeed a form of Panpsychism (PS), though not the only kind.
The alternatives that Schick's article leaves us are Subjective Mentalism (SM), Transcendental Idealism, Bohm's unbroken wholeness, and Pluralistic Idealism. Besides the alternatives that Schick suggests, there are some others. In The Dancing Wu Li Masters, Gary Zukav tells us that the assumptions at work in Bell's Theorem are locality and contrafactual definiteness. Locality is the believe that nothing can travel faster than light, and I have already discussed why it is not threatened. Contrafactual definiteness is the belief that the world is one way and no other, but that it could have been different if something different had happened in the past. There are two ways in which contrafactual definiteness could be false, for there are two parts to it. These are contrafactualness and definiteness. Contrafactualness is the belief that the present would be different if the past had been different, and definiteness is the belief that the world is one way and not another. According to Zukav, superdeterminism is true if contrafactualness is false, and the multiple worlds theory is true if definiteness is false.
Superdeterminism is more like predestination than regular determinism. According to regular determinism, everything is what it is because of the laws of nature and because of what the universe was in the past. In fact, it implies and depends upon contrafactualness. For superdeterminism, the present couldn't be anything other than it is, and there is no causal connection between it and the past. Thus, to deny contrafactualness is to deny causation. Since we would have to give up science if we gave up causation, it would be very difficult to give up contrafactualness.
Definiteness is the belief that the world is only one way and no other. It seems to be a way of saying that you can't have your cake and eat it, too. If it is false, claims Zukav, the universe is constantly splitting into multiple worlds. For example, the universe might split into a world in which you eat your cake, and into one in which you do not. It would seem that to deny definiteness is to deny the law of noncontradiction.
In fact, I believe that it gives us reason to prefer OM. Since science consists in the study of an external, objective world, mentalism is opposed to science. Therefore, the scientist who believes mentalism is trying to have his cake and eat it too.
Given that science gives us no reason to prefer SM, there is an even better reason to believe OM. OM can explain why the world seems objectively the same to different observers, but SM cannot. In order for the world we experience to seem objective, it must either exist independently from any mind (i.e. be objective), or its identity must depend upon the beliefs of one mind or a consensus of minds. Since OM holds that there is one ideal observer whose beliefs determine what it true, it better explains our experience than SM does. Furthermore, it can account for the spin-measurement experiment results just as easily, for everything is possible with God. Therefore, OM fares better than SM.
Although CM accounts for the similarity between observations better than SM does, OM still accounts for it better. For CM, facts about the world are apt to change when a certain number of minds change their minds or die. CM also puts a damper on our ability to discover facts about the world. For example, no one should have discovered that the earth is round if CM is true. After all, it was discovered to be round when most people thought it was flat. If, however, the world was always round in the mind of God, then there is no problem in accounting for the discovery of that fact. Thus OM fares better than CM. So, it can be regarded as the best mentalist theory.
FP, by contrast, is very much concerned with what goes on under the skin, and it does call it mental. This does not place it in the Supervenience camp, though, for it defines the mental in terms of behavior. BP regards the entire person as a black box that receives stimuli and emits responses, and FP simply goes a step further by regarding a mental event as a black box that performs certain functional roles in the determination of behavior. Just as BP is not concerned with what goes on inside a person, FP is not concerned with what goes on inside a "mental" event. To be more precise, it is concerned with what goes on in a "mental" event, but only to the extent that it can be analyzed into events that play simpler functional roles in determining behavior. FP stops when the analysis of a "mental" event will be into something other than other "mental" events.
Whereas BP identifies a person's "mental" life with her behavior, FP identifies it with a complex pattern of functional roles. Accordingly, FP may be understood by referring to it as Homunculi Behaviorism. This is because FP imagines an agent to be an organization of entities that can be understood in the same way that BP understands the entire person. Since the difference between FP and BP is that FP offers a richer and more comprehensive account of a person's behavior, I would say that FP is a much better theory.
that if someone desires that p, and this desire is not overridden by other desires, and he believes that an action of kind K will bring it about that p, and he believes that such an action is within his power and is a preferable way to bring it about that p, then certeris paribus, the desire and the beliefs will cause him to perform an action of kind K. (Horgan & Woodward, p.197)In order to reject Folk Psychology and embrace EP, we have to believe that there are no beliefs and desires, and that people are not rational. So, by EP's own standards, there is no way to believe it. For you cannot believe that there are no beliefs without falling into contradiction. It is still conceivable that someone could believe EP, though, for anyone who believes it is irrational, and it does claim that people are not rational.
In case this is a straw man, however, I wish to also discuss a weaker version of EP. This version holds that there are beliefs and desires, but that an explanation of behavior in terms of them is still terribly inadequate. It holds that neurophysiology is a much better base for predicting behavior. It is probably true that neurophysiology will serve better in some instances than will Folk Psychology. For example, it might better explain why some fellow pathologically washes his hands all the time, and why paint fumes can make a man kill a woman. These, however, are cases when something goes wrong. When people don't have their heads messed up, their behavior can be predicted fairly well from a knowledge of their beliefs and desires.
Since the main difference between EP and FP is that EP attacks Folk Psychology, and since it does a poor job of it, I must conclude here that FP fares better than EP. Therefore, FP is the best physicalist theory.
PE is false, for empiricism is false, and abstract knowledge does not refer to anything that is immediately sensible. In what is an unsuccessful argument for rationalism in his second Meditation, Descartes succeeds in discrediting empiricism. He tells us that he has a piece of beeswax, and he describes what his senses tell him about it. He then melts the wax, so that all his sensations of it change. If he knew of the wax only through his sensations of it, he claims, then he would not know that he holds the same piece of wax, for there are no sensations to indicate that it is the same. He concludes that he knows the wax through reason, not through his senses. He is right to conclude that he knows the wax through his reason, but wrong to conclude that he does not know it through his senses. His senses told him that he held something with certain characteristics. But it took his reason to integrate his senses and tell him what he held. It was his reason that told him he held the same piece of wax, but his senses that told him he held anything at all. The point here is that reason is required for knowledge about the world. It is not the source of our knowledge, but it is necessary for it. Since reason is required for knowledge about the world, it cannot be true that knowledge comes from sensation alone. Thus, empiricism is false.
Since empiricism is false, there is no ground for believing PE. Furthermore, it can be shown that the world of forms does not exist. A form is non-physical but objective. The form of a circle, for instance, is the same for everyone who understands it. The ratio between a circle's circumference and radius does not depends upon what any mathematician believes it is. This is not because an ideal circle resides in a world of forms, but because the qualities of a circle logically follow from its description. Furthermore, we cannot tell whether anything is a circle unless we compare it to our understanding of what a circle is. If we encountered the ideal circle that is supposedly in the world of forms, we would have to compare it too to our understanding of a circle before we knew it was one. Consequently, our understanding of forms cannot come from any vision of another world. Since the inhabitants of the world of forms are supposed to be the standards by which we judge whether anything is an instantiation of a particular form, and since we must depend upon our understanding of descriptions as our standard instead, it follows that there is no world in which our standards reside separately from their instantiations. Therefore, there is no world of forms, and PE is false.
In his paper, Fergus Duniho correctly reproduced one of my assertions. I did
claim, as he noted, that the ``Bell experiment'' compels us to drop one (at
least) out of three basic assumptions. Unfortunately, he then wrote :
``The easiest one to let go, he [d'Espagnat] believes, is the first, that an
external world exists independently of our consciousness''. This statement is
factually wrong. In fact, even a quick look at any one of my books
(Conceptual Foundations of Quantum Mechanics, 2d edition,
Addison-Wesley, Reading, MA, 1976, Reality and the Physicist, Cambridge
University Press,1989, Veiled Reality, Addison Wesley, 1995,...) or
just at my Scientific American article (Nov.1979, p.158) would reveal
(see e.g. Sc. Am., pages 178, 180) that the assumption I always
considered to be ``the easiest one to let go'' is not the first but the
third one in the said list (that nothing, not even mere ``influences'',
can travel faster than light, also called ``Einsteinian separability'').
Consequently, Duniho's criticisms concerning my standpoint ``apparently, it
has not occurred to d'Espagnat...'' etc.) are utterly irrelevant.