The Argument from Causality by N. Fakhr - HTML preview
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Week Twelve: Determinism and Free Will—Does Quantum Physics Offer a Way Out of Determinism?
Believer: “I was in a bit of a hurry last week and didn’t have a chance to respond to you. You probably left here feeling victorious. If so, I have to say: don’t get your hopes up.”
Skeptic laughed and said, “That depends on what I consider a victory...”
Believer: “Do you remember using the findings of quantum physics to undermine the argument for the existence of the soul1?”
Skeptic: “Yes, absolutely!”
Believer: “Well, now it’s my turn to use the uncertainty surrounding the findings of quantum physics against absolute determinism. As you said, we do not know the nature of matter or existence. Perhaps things happen at the quantum level that could cast the question of determinism and free will in a different light.
“I admit that I don’t know much about the subject, but I do know that some philosophers and physicists have concluded that quantum physics might hold a solution to the problem of free will.”
Skeptic: “At the beginning of our discussion, you said that causality concerns existence and nonexistence, not qualities. You said that anything to which the word ‘thing’ can be applied ‘exists,’ while anything else is ‘nonexistence’—and nonexistence does not actually exist. So we can speak only of what ‘exists.’ You said that anything that is a phenomenon, regardless of its qualities, stands in need of a cause solely by virtue of being a phenomenon. You said that the qualities of a phenomenon have no bearing whatsoever on its need for a cause and cannot make it independent of one.
“‘Apparently,’ causality does not hold at the quantum level. This means that, ‘apparently,’ at the quantum level, earlier phenomena are not the causes of later phenomena. ‘For you2,’ this means the following: although phenomenon A is not caused by the phenomenon preceding it, it must nevertheless have a cause. Therefore, either its cause is some phenomenon other than the one preceding it, or its cause is directly the Necessary Existent itself. In other words, at the quantum level, the Necessary Existent creates phenomena one by one and in succession, like an animator. This is precisely why, at the quantum level, we apparently see no causal connection between two successive phenomena.
“Even if our desires and acts of will are governed by this kind of animation-like creation, they would still be directly created by the Necessary Existent, and the same problem of causal determinism would still apply to them. We’ve already considered this possibility.”
Believer: “Perhaps you’re right, but until I understand what actually happens at the quantum level, I can’t be sure that the secret of human free will isn’t hidden at the ‘quantum level’—especially since I’ve heard that some philosophers and scientists, after learning about what happens at the quantum level, began to wonder whether these very quantum events might show that we have free will. So I think we should examine the issue more closely3.”
Skeptic: “So you think it might be possible that, when it comes to quantum phenomena, the Necessary Existent plays no role in their creation—neither as the starting point of a causal chain nor as the animator? Very well... then you’re admitting that phenomena can come into existence without the Necessary Existent.”
Believer: “I’m not saying that anything can happen outside those two possibilities. I only want to know whether something might happen at the quantum level that could somehow resolve the problem of determinism and free will. On the face of it, you seem to have the stronger case; but perhaps there is a solution hidden somewhere that we have overlooked.”
Skeptic: “If you remember, in the double-slit experiment with electrons, we saw that appearances seem to suggest that an object such as an electron does not exist in the way we had previously imagined. Apparently, there is no object with a definite size, position, and velocity moving toward a definite point like a tiny pellet. Rather, it seems as though a wave of the ‘probability of an electron’s presence’ travels throughout space. This wave passes through both slits, producing two waves that interfere with each other: at some points they reinforce one another, while at others they cancel each other out. In this way, they determine at which points on the detector screen the electron is more likely to strike and manifest itself, and at which points it is less likely—or not at all—to do so.”
Believer: “Couldn’t a single electron manifest itself at more than one point? After all, there are countless points at which the electron has some probability of being present; that is, its probability of being present at countless points is greater than zero. Why shouldn’t the electron appear at more than one point, just as the water waves in your example struck the wall beyond the two slits at more than one point?”
Skeptic: “Apparently, in some unknown way, the electron has to choose one out of all the points at which it could manifest itself. Sometimes it chooses points where the probability of detection is low, but most of the time it chooses points where that probability is high.
“As soon as the electron chooses one point at which to appear, it will no longer appear at any of the other points.”
Believer: “Every wave has a wavelength, frequency, velocity, and amplitude. The amplitude of a wave—or the height of the water waves in your example—varies with time and position, and the wave function is a function that gives the variation in amplitude with respect to time and position. Do these probability waves have those properties as well?”
Skeptic: “The Schrödinger wave equation gives us a function that determines the amplitude, or magnitude, of the probability of matter being present as a function of changes in time and position. This equation explains quantum phenomena very well and predicts them with great accuracy.”
Believer: “Wait... is it only ‘we’ who don’t know where the electron will appear, or is there intrinsically no definite point at which the electron will appear? What I mean is this: Is the uncertainty about the electron’s position merely the result of our inability to predict where it will appear, so that we use ‘probability waves’ simply as a convenient way of describing these phenomena and statistically predicting the electron’s presence? Or is there really such a thing as a ‘probability of the presence of matter’ that literally propagates through space as a wave?”
Skeptic: “If we didn’t observe an interference pattern, we might be more inclined to say, ‘It is simply we who cannot predict the electron’s position,’ and that ‘no wave of probability actually exists in physical reality.’
“But the fact that we do observe an interference pattern pushes us toward the belief that ‘there really is a wave of probability in physical reality,’ one that even produces the interference pattern. All things considered, though, we cannot say with certainty what is really going on.”
Believer: “Why did some philosophers think that these quantum observations might explain free will?”
Skeptic: “I think it has to do with the history of the debate over determinism and free will.”
Predestination, Deterministic Necessity, and Quasi-Predestination
Skeptic: “From ancient times right up to the present, many people have believed that our fate is predetermined and that we have no power to escape it. Those who have held, and still hold, such a belief think that the time of our death—our appointed hour, so to speak—is fixed and that we cannot escape it. They likewise believe that what will happen to us, at what time and in what place, has already been determined and cannot be avoided; even what kind of person we will become, good or bad, has been determined for us in advance. Naturally, this ‘destiny’ is determined by heavenly powers or by God. For example, verse 143 of Surah An-Nisa says:
مُذَبْذَبينَ بَيْنَ ذلِکَ لا إِلي هؤُلاءِ وَ لا إِلي هؤُلاءِ وَ مَنْ يُضْلِلِ اللَّهُ فَلَنْ تَجِدَ لَهُ سَبيلاً
“That is: They waver between the two, belonging neither to these nor to those [neither among the believers nor among the unbelievers]; and whomever God leads astray, you will never find a way for him.
“Belief in this kind of determinism has existed since ancient times.”
Believer: “Then we could say that determinism is endorsed by the Quran as well.”
Skeptic: “No, that’s not the case. The kind of determinism endorsed by the Quran, or believed in by people since ancient times, is ‘predestinarian determinism.’ Under predestinarian determinism, even if you know what has been destined for you, you cannot escape it. Your wishes and efforts have no effect on your ability to evade what has been predestined. In this form of determinism, heavenly powers may use your own efforts to bring about what they intend, or they may simply disregard all your efforts and struggles and do whatever is necessary to bring about what they have willed. In other words, there is no precise and universal rule or law governing how this happens. Predestinarian determinism may unfold in accordance with our wishes or contrary to them. What has been predestined may come to pass despite our reluctance.
“Belief in this kind of determinism entails believing that God is ‘directly’ involved in the occurrence of every phenomenon. In other words, God can directly decide whether the bud in this flowerpot will open tomorrow or not; therefore, whether it will open is not predictable. To bring about what He has predestined, He may command the bud to open tomorrow, or He may command it not to open.
“On this view, there is no fixed law or rule governing the relation between phenomena; everything is in the hands of gods or heavenly powers. If someone wants to change their destiny, they must appeal to those very heavenly powers. On this view, saying ‘Inshallah’4—in its supplicatory sense—about whether this bud will open makes sense, because even if you knew every detail of the present conditions, you still could not predict whether the bud would open tomorrow: you would not know whether God has willed it to open. Under predestinarian determinism, everything is in the hands of a heavenly power, and the will of that heavenly power is ‘unpredictable.’ What has been predestined is known only to God.”
Believer was staring at the bud in the flowerpot. After a few seconds, he said, “I see what you mean. You divide determinism into two possible kinds:
“One is ‘predestinarian determinism,’
“and the other is ‘deterministic determinism.’
“Under deterministic determinism, or causal determinism, definite laws and regularities govern successive phenomena, and if you have complete knowledge of the present, you can accurately predict the future. At the same time, whether you want something or do not want it, this ‘want’ of yours can become part of the chain of phenomena and influence the formation of the final outcome, thereby changing what you would otherwise have predicted.
“Under deterministic determinism, what you want can affect what happens, even though what you will want and how that desire will affect the final outcome have themselves been determined from eternity.”
Skeptic: “Exactly. Under deterministic determinism, even if everything is directly created by the Necessary Existent acting as an animator, the ‘law-governed regularity’ among successive phenomena means that even the Necessary Existent itself cannot change what it has willed from eternity. Anyone who could obtain all the information about the present moment would be able to predict the future accurately. Under deterministic determinism, saying ‘Inshallah’ in its supplicatory sense has no meaning; it is the laws governing the relations among phenomena that determine what will happen in the future.
“Under predestinarian determinism, our efforts do not necessarily have any effect within the causal chain: whatever has been predestined to happen will happen, and God’s will and decree can deliberately override our desires, acts of will, and efforts and render them ineffective. Under deterministic determinism, by contrast, our efforts are themselves part of the chain of phenomena, and what happens may therefore depend on our desires, acts of will, and actions.”
Believer: “Now, what does this have to do with the conclusion reached by philosophers who thought quantum theory might offer a solution to the problem of free will?”
Skeptic: “After the discovery of the laws of physics and before the development of quantum theory, many people, observing the regularities that govern nature, concluded that our desires and acts of will are also governed by the laws of physics and, like any other phenomenon, are predetermined and predictable. They understood this determination in terms of deterministic necessity. Deterministic necessity, or determinism, was virtually the only form of necessity discussed by some philosophers, and the universal laws of physics were regarded as evidence for it.
“Whether what we will desire and what we will will are known in advance was one of the important conclusions that some philosophers attributed to the findings of physics. They regarded our minds and brains as material and therefore subject to the laws of physics, and they placed considerable emphasis on this point.
“Advocates of free will, on the other hand, thought that if they could somehow show that determinism might break down at the level of mental and neural processes, they could restore freedom of the will.
“With the findings of quantum theory and the introduction of chance and randomness into quantum events, it seemed that a significant breach had opened up in determinism. If such quantum events played a role in the formation of our acts of will, then it could no longer be said that our acts of will had been determined from eternity. This was regarded as a possible route back to free will—a will that could not be predicted.”
Believer: “So a way out was finally found. Right?”
Skeptic: “We cannot say that this route establishes the kind of freedom of will that would place full responsibility on human beings while removing responsibility from the Necessary Existent.”
Believer: “Why? What’s the problem with it?”
Skeptic: “Look... when probability enters into quantum phenomena, it means that if, at time t1, an electron is at position x1, chance and randomness determine at which point the electron will be found at time t2.”
Believer: “You mean that even if we knew the electron’s position, velocity, and direction of motion at time t1, we still couldn’t determine precisely where the electron would be at time t2?”
Skeptic: “Of course, according to Heisenberg’s uncertainty principle, we cannot know both the electron’s exact velocity and its exact position at time t1. But quite apart from the impossibility of determining both the electron’s position and velocity simultaneously at a given moment, the electron’s position at time t2 is itself governed by a wave of probability. It is as though your Necessary Existent, too, must—as Einstein put it—‘throw dice’5 to determine where to place the electron at time t2, or where to create it.”
Believer: “So even the Necessary Existent cannot know where it will bring the electron into existence?”
Skeptic: “Whether it can or cannot know is not our concern. The important point is that, apparently, phenomenon number one—the electron at position x1 at time t1—is not the sufficient cause of the next phenomenon. If it were, only one outcome would be predictable; that is, there would be only one position at which the electron at time t2 could appear. Yet the Schrödinger wave function tells us that the electron’s position at time t2 cannot be specified; we can determine only the probabilities of finding the electron at different points.
“This has nothing to do with our having insufficient information about the state of affairs at time t1.
“In short, it appears that at the quantum level there is no causal relation between phenomena, and causality in its deterministic form—the form in which a chain of causes and effects gives rise to determinism—breaks down.
“What theories scientists have proposed to solve this problem, and whether those theories have succeeded, is not our concern here. What matters for our discussion is that, assuming chance and probability are intrinsic to quantum events and determinism breaks down at the quantum level, we must accept that phenomenon number one does not cause phenomenon number two. Rather, the phenomena bear no causal relation to one another, and no precise regularity operates at the quantum level.
“This means that if we still want to invoke the Necessary Existent to explain such a state of affairs, we have to accept that the Necessary Existent is not merely the ‘starting point of the chain of causes.’ In addition to standing at the head of that chain, it must act like an animator, intervening at every moment and directly deciding which events to create. It is the Necessary Existent that must decide, each time and at every moment, where to create the electron. Of course, it does not have complete freedom in doing so. Although it can make any decision regarding any individual electron and create it wherever it wishes, when dealing with large numbers of electrons, its decisions must collectively conform to the Schrödinger wave equation. The overall distribution of electrons and other elementary particles must turn out in such a way that, at scales above the quantum level, everything appears deterministic, law-governed, and predictable.”
Believer: “All right... so does this finally solve the problem of determinism or not?”
Skeptic: “If we assume the intervention of an animator in the way I’ve just described, the only conclusion is that even if our desires and acts of will cannot be predicted in advance and do not obey deterministic necessity, they will still be subject to predestinarian necessity. In other words, although it may be impossible to predict what we will will, whatever we do will is the product of the animator’s will.
“Now, as a philosophical exercise, let’s remove the animator from the quantum level as well. And, with a deliberately exaggerated magnifying glass, let’s magnify the influence of quantum phenomena on the macroscopic world and extend the randomness of quantum events to the randomness of our acts of will. We’ll see that it still makes no difference. The result is the same.”
Believer: “How can it make no difference?”
Skeptic: “When there is no causality of any kind, even if it is known what I desire at this moment, there is no way of knowing what I will will in the next moment, or whether my act of will will have anything to do with my desire. That is because we have assumed that my act of will is the product of random events at the quantum level and has no direct connection with my present desire—the phenomenon that preceded it. My act of will could be anything, just as the electron might be created anywhere without any precise relation to where it was before.
“For example, phenomenon number one is that I desire to drink this tea. But the next phenomenon—my act of will—is created randomly, and I might, for instance, will to throw my pen at the window.
“You see, looking to the quantum world for a solution not only fails to produce the kind of free will that entails responsibility, but leads instead to an unrestrained form of predestinarian necessity. If we remove the animator as well, we can call it ‘quasi-predestinarian necessity.’ Quasi-predestinarian necessity resembles predestinarian necessity in that the future cannot be predicted. It differs from predestinarian necessity in that even the Necessary Existent cannot know what will spontaneously emerge from nonexistence. Under this form of necessity, nothing is predictable, and everything is not only beyond our control but even beyond the control of the Necessary Existent.”
Believer: “Do you mean those philosophers had failed to notice these points?”
Skeptic: “I don’t know. All I know is that they took the presence of determinism—which results in ‘only one possible and predictable choice’—to mean the absence of free will, and the absence of determinism—which allows ‘more than one possible choice and therefore makes the choice unpredictable’—to mean freedom of the will. Perhaps the question of responsibility in the afterlife was not what they had in mind.
“We are examining the issue from the standpoint of whether a Day of Judgment can be rationally justified. Therefore, the possibility of more than one outcome does not solve the problem of responsibility in the afterlife. Rather, it is the manner in which the choice comes into existence that would have to provide a way to justify the Day of Judgment. But we have seen that no possible mode of creation can provide a justification for the story of heaven and hell and divine punishment.
“In any case, quantum theory offers no solution for the heaven and hell of religions.
“Either predestinarian necessity, deterministic necessity, or quasi-predestinarian necessity...
“There is no escape from these three. You can call the first two forms of causal necessity, because they are products of causality. The third can be called non-causal necessity, because although it is not the product of causality, there is nevertheless no escape from whatever it randomly and spontaneously brings into existence, and neither we nor anyone else bears responsibility for whatever it produces.
“Under predestinarian necessity, there is not necessarily any causal connection between desire, act of will, action, and outcome. Everything is created irregularly by the Necessary Existent acting as an animator. The animator is the cause of everything, and nothing is predictable in advance. Sometimes it creates B after A; at other times, it creates something other than B after A. Seeing A gives us no assurance that B will come into existence.
“Under deterministic necessity, there is a connection between desire, act of will, action, and outcome, but all of them have been determined from eternity, and with complete knowledge of the present, the future can be predicted. The relation between phenomena under this kind of necessity may be causal or non-causal. If the Necessary Existent merely stands at the head of the chain of causes and effects, the relation between phenomena is causal. If the Necessary Existent operates solely through ‘law-governed animation,’ the relation between phenomena is not causal. Either way, B is always created after A, and upon observing A, one can correctly predict that B will come into existence.
“Under quasi-predestinarian necessity—which, of course, we previously rejected on the basis of the argument from causality—phenomena spontaneously emerge from nonexistence, with no connection either to the preceding phenomenon or to the Necessary Existent. Neither we nor the Necessary Existent can know what will happen next. No one knows what will come into existence after A. Whatever spontaneously emerges from nonexistence cannot make anyone responsible or deserving of reward or punishment.
“There is no other possible mode of creation. Therefore, there is no escape from necessity, nor is there any way to provide a rational justification for the Day of Judgment.”
Is There Something Between Complete Determinism and Complete Free Will?
Believer: “Don’t you think there might be something between complete determinism and complete free will, and that our desires and acts of will may not be quite as determined as you think?”
Skeptic: “You mean that both we and the Necessary Existent are responsible for our actions?”
Believer: “Yes.”
Skeptic laughed. “So for every sin, we get fifty percent of the punishment and God gets the other fifty percent? After all, in every act of will and every action of ours, he bears some responsibility too, doesn’t he? He too would be responsible for the creation of evil and could no longer be called ‘absolutely good.’ In fact, this isn’t a solution that does you any good.”
Skeptic continued: “Keep in mind that we’re not politicians whose main concern is to come up with something that will send everyone home happy and satisfied—determinists and believers in free will alike—while trying to please both sides. We’re having a philosophical discussion, and we’re trying to solve the puzzle. We’re not supposed to make concessions merely to keep everyone happy.
“Causality has only one implication: every phenomenon is, wholly and completely—not partially—the product of its cause. Our act of will is no exception. Our act of will, too, is wholly and completely a phenomenon, and is the product of its cause.”
Believer and Skeptic both fell silent for several minutes. Skeptic slowly drank a cup of tea as he gazed outside. He placed the cup back on its saucer, turned to Believer, and said:
“Do you think there’s any point in continuing this discussion?”
Could the Necessary Existent Have Granted Us the Freedom to Choose?
Believer: “Yes, of course! I think perhaps we could say that God may have granted us the freedom to make choices on our own, independently of him. He knows what choices we will make, but he has given us permission to exercise our will without depending on him.”
Skeptic looked at Believer incredulously and said, “Don’t you think what you’ve just said contradicts the entire argument for causality that you laid out at the beginning? You said that a phenomenon, simply by virtue of being a phenomenon, requires a cause. If a phenomenon does not yet exist and has not yet come into being, how can it be given permission to bring itself into existence?
“You said that we cannot point to nothingness; we cannot speak of nothingness—and you were right. Now we can add that permission cannot be given to nothingness, nor can permission be withheld from it. Nothingness does not exist at all, let alone be something that can be permitted to bring itself into existence—or forbidden from doing so.”
Believer: “I didn’t say God gave permission to nothingness. I said God gave human beings permission to make the choice themselves.”
Skeptic: “Do you think you can logically propose a mechanism for this notion of ‘permission granted by God’ that would somehow produce a new possibility outside the law of causality?
“Do you think there is some way—some clever device—by which you could sever the connection between the Necessary Existent and a phenomenon? Can we logically conceive of a situation in which a phenomenon comes into existence without the involvement of the Necessary Existent? A situation in which the Necessary Existent is neither at the head of the chain of causes leading to that phenomenon nor directly creating it, like the animator?
“Remember, the whole reason we appealed to a Necessary Existent in the first place was that we had concluded, as a matter of logic, that it is impossible for a phenomenon to come into existence on its own or without some connection to the Necessary Existent. Now, if you say that a phenomenon can come into existence outside this rule provided only that the Necessary Existent gives it permission to do so, then you are conceding that even without a Necessary Existent, it is possible for a phenomenon—or a universe, or multiple universes—to come into existence.
“The Necessary Existent cannot grant permission for something logically impossible to occur. Nor can it exempt a phenomenon—which, directly or indirectly, must in any case depend upon the Necessary Existent—from that dependence.
“I think introducing the phrase ‘permission from the Necessary Existent’ is merely a play on words; it cannot break the law of causality. Even if causality could somehow be broken and the Necessary Existent could step aside, then, as I said before, our acts of will and our actions would simply spring into existence out of nothing, without requiring a cause—and once again, we would not be responsible for bringing them into existence.
“Your proposal—that the Necessary Existent grants human beings permission to choose independently of it and outside the causal chain—is just another version of the proposal you made earlier: devising a mechanism for circumventing causality so as to make room for ‘free will while absolving God of responsibility.’ As I said before, whatever mechanism you propose will ultimately have to operate within causality. Mechanisms do not have the special property of bypassing causality; they merely describe how phenomena occur, and in what sequence they are arranged, so as to produce the final phenomenon.”
Believer: “It is true that logical reasoning leads us to determinism, but we do not experience determinism directly—we do not feel it. Even someone who proves determinism lives, at the level of immediate experience, on the assumption that he has free will. Free will, however, which we apprehend quite readily through direct, immediate awareness, cannot be established philosophically.”
Skeptic rested his face against the palm of his hand and looked at Believer in a way that suggested he was growing tired of the argument and no longer had much energy to continue.
Believer: “Why are you looking at me like that? Am I saying anything other than what is actually the case?”
Skeptic: “I told you already... by ‘determinism,’ I do not mean psychological compulsion—the feeling that one is being forced or acting against one’s will. When a chain of causes, or the animator, or chance, or any other external cause produces the phenomena ‘I desire,’ ‘I will,’ and ‘I act,’ then of course, under those circumstances, I should experience myself as choosing freely. I should feel, with my whole being, that the desire is my desire, the act of will is my act of will, and my action accords with my desire and my will. In none of this should I experience anything other than freedom.
“In fact, free will simply means:
“I desire A;
“I will to do A;
“I do A.
“Causal determinism says that all three of these ‘I’s are brought into existence, directly or indirectly, by the Necessary Existent. According to the conclusions of the causal argument, it is not that the Necessary Existent merely creates ‘my desire,’ leaving me to experience that desire as something alien to myself. Rather, the Necessary Existent—or nature, or whatever name you want to give it—creates the entire phenomenon of ‘I desire.’ In other words, it creates the ‘self,’ the ‘I,’ or the ‘consciousness’ that is experiencing the desire. So there is nothing surprising about the fact that you never experience your own desire as something alien or regard it as something imposed upon you from outside.
“Be careful not to let the use of a single word in two different senses mislead you. And if it does, you certainly won’t be the only one to make that mistake. Nearly all thinkers who oppose causal determinism seem strangely insistent on slipping the psychological meaning of ‘compulsion’ into their arguments—taking it to mean reluctance or being forced to act against one’s own desire—and then concluding that because we do not experience that kind of compulsion, determinism must therefore be false.”
Believer: “I’m tired! Let me think about everything we’ve discussed so far, and we’ll continue next week.”
Skeptic: “Until next week, then.”