Predictive Processing and Free Will

Our model of the mind as an embodied predictive engine explains why people have a sense of free will, and what is necessary for a mind in general in order to have this sense.

Consider the mind in the bunker. At first, it is not attempting to change the world, since it does not know that it can do this. It is just trying to guess what is going to happen. At a certain point, it discovers that it is a part of the world, and that making specific predictions can also cause things to happen in the world. Some predictions can be self-fulfilling. I described this situation earlier by saying that at this point the mind “can get any outcome it ‘wants.'”

The scare quotes were intentional, because up to this point the mind’s only particular interest was guessing what was going to happen. So once it notices that it is in control of something, how does it decide what to do? At this point the mind will have to say to itself, “This aspect of reality is under my control. What should I do with it?” This situation, when it is noticed by a sufficiently intelligent and reflective agent, will be the feeling of free will.

Occasionally I have suggested that even something like a chess computer, if it were sufficiently intelligent, could have a sense of free will, insofar as it knows that it has many options and can choose any of them, “as far as it knows.” There is some truth in this illustration but in the end it is probably not true that there could be a sense of free will in this situation. A chess computer, however intelligent, will be disembodied, and will therefore have no real power to affect its world, that is, the world of chess. In other words, in order for the sense of free will to develop, the agent needs sufficient access to the world that it can learn about itself and its own effects on the world. It cannot develop in a situation of limited access to reality, as for example to a game board, regardless of how good it is at the game.

In any case, the question remains: how does a mind decide what to do, when up until now it had no particular goal in mind? This question often causes concrete problems for people in real life. Many people complain that their life does not feel meaningful, that is, that they have little idea what goal they should be seeking.

Let us step back for a moment. Before discovering its possession of “free will,” the mind is simply trying to guess what is going to happen. So theoretically this should continue to happen even after the mind discovers that it has some power over reality. The mind isn’t especially interested in power; it just wants to know what is going to happen. But now it knows that what is going to happen depends on what it itself is going to do. So in order to know what is going to happen, it needs to answer the question, “What am I going to do?”

The question now seems impossible to answer. It is going to do whatever it ends up deciding to do. But it seems to have no goal in mind, and therefore no way to decide what to do, and therefore no way to know what it is going to do.

Nonetheless, the mind has no choice. It is going to do something or other, since things will continue to happen, and it must guess what will happen. When it reflects on itself, there will be at least two ways for it to try to understand what it is going to do.

First, it can consider its actions as the effect of some (presumably somewhat unknown) efficient causes, and ask, “Given these efficient causes, what am I likely to do?” In practice it will acquire an answer in this way through induction. “On past occasions, when offered the choice between chocolate and vanilla, I almost always chose vanilla. So I am likely to choose vanilla this time too.” This way of thinking will most naturally result in acting in accord with pre-existing habits.

Second, it can consider its actions as the effect of some (presumably somewhat known) final causes, and ask, “Given these final causes, what am I likely to do?” This will result in behavior that is more easily understood as goal-seeking. “Looking at my past choices of food, it looks like I was choosing them for the sake of the pleasant taste. But vanilla seems to have a more pleasant taste than chocolate. So it is likely that I will take the vanilla.”

Notice what we have in the second case. In principle, the mind is just doing what it always does: trying to guess what will happen. But in practice it is now seeking pleasant tastes, precisely because that seems like a reasonable way to guess what it will do.

This explains why people feel a need for meaning, that is, for understanding their purpose in life, and why they prefer to think of their life according to a narrative. These two things are distinct, but they are related, and both are ways of making our own actions more intelligible. In this way the mind’s task is easier: that is, we need purpose and narrative in order to know what we are going to do. We can also see why it seems to be possible to “choose” our purpose, even though choosing a final goal should be impossible. There is a “choice” about this insofar as our actions are not perfectly coherent, and it would be possible to understand them in relation to one end or another, at least in a concrete way, even if in any case we will always understand them in a general sense as being for the sake of happiness. In this sense, Stuart Armstrong’s recent argument that there is no such thing as the “true values” of human beings, although perhaps presented as an obstacle to be overcome, actually has some truth in it.

The human need for meaning, in fact, is so strong that occasionally people will commit suicide because they feel that their lives are not meaningful. We can think of these cases as being, more or less, actual cases of the darkened room. Otherwise we could simply ask, “So your life is meaningless. So what? Why does that mean you should kill yourself rather than doing some other random thing?” Killing yourself, in fact, shows that you still have a purpose, namely the mind’s fundamental purpose. The mind wants to know what it is going to do, and the best way to know this is to consider its actions as ordered to a determinate purpose. If no such purpose can be found, there is (in this unfortunate way of thinking) an alternative: if I go kill myself, I will know what I will do for the rest of my life.

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Chastek on Determinism

On a number of occasions, James Chastek has referred to the impossibility of a detailed prediction of the future as an argument for libertarian free will. This is a misunderstanding. It is impossible to predict the future in detail for the reasons given in the linked post, and this has nothing to do with libertarian free will or even any kind of free will at all.

The most recent discussions of this issue at Chastek’s blog are found here and here. The latter post:

Hypothesis: A Laplacian demon, i.e. a being who can correctly predict all future actions, contradicts our actual experience of following instructions with some failure rate.

Set up: You are in a room with two buttons, A and B. This is the same set-up Soon’s free-will experiment, but the instructions are different.

Instructions: You are told that you will have to push a button every 30 seconds, and that you will have fifty trials. The clock will start when a sheet of paper comes out of a slit in the wall that says A or B. Your instructions are to push the opposite of whatever letter comes out.

The Apparatus: the first set of fifty trials is with a random letter generator. The second set of trials is with letters generated by a Laplacian demon who knows the wave function of the universe and so knows in advance what button will be pushed and so prints out the letter.

The Results: In the first set of trials, which we can confirm with actual experience, the success rate is close to 100%, but, the world being what it is, there is a 2% mistake rate in the responses. In the second set of trials the success rate is necessarily 0%. In the first set of trials, subject report feelings of boredom, mild indifference, continual daydreaming, etc. The feelings expressed in the second trial might be any or all of the following: some say they suddenly developed a pathological desire to subvert the commands of the experiment, others express feelings of being alienated from their bodies, trying to press one button and having their hand fly in the other direction, others insist that they did follow instructions and consider you completely crazy for suggesting otherwise, even though you can point to video evidence of them failing to follow the rules of the experiment, etc.

The Third Trial: Run the trial a third time, this time giving the randomly generated letter to the subject and giving the Laplacian letter to the experimenter. Observe all the trials where the two generate the same number, and interate the experiment until one has fifty trials. Our actual experience tells us that the subject will have a 98% success rate, but our theoretical Laplacian demon tells us that the success rate should be necessarily 0%. Since asserting that the random-number generator and the demon will never have the same response would make the error-rate necessarily disappear and cannot explain our actual experience of failures, the theoretical postulation of a Laplacian demon contradicts our actual experience. Q.E.D.

The post is phrased as a proof that Laplacian demons cannot exist, but in fact Chastek intends it to establish the existence of libertarian free will, which is a quite separate thesis; no one would be surprised if Laplacian demons cannot exist in the real world, but many people would be surprised if people turn out to have libertarian free will.

I explain in the comments there the problem with this argument:

Here is what happens when you set up the experiment. You approach the Laplacian demon and ask him to write the letter that the person is going to choose for the second set of 50 trials.

The demon will respond, “That is impossible. I know the wave function of the universe, and I know that there is no possible set of As and Bs such that, if that is the set written, it will be the set chosen by the person. Of course, I know what will actually be written, and I know what the person will do. But I also know that those do not and cannot match.”

In other words, you are right that the experiment is impossible, but this is not reason to believe that Laplacian demons are impossible; it is a reason to believe that it is impossible for anything to write what the person is going to do.

E.g. if your argument works, it proves either that God does not exist, or that he does not know the future. Nor can one object that God’s knowledge is eternal rather than of the future, since it is enough if God can write down what is going to happen, as he is thought to have done e.g. in the text, “A virgin will conceive etc.”

If you answer, as you should, that God cannot write what the person will do, but he can know it, the same applies to the Laplacian demon.

As another reality check here, according to St. Thomas a dog is “determinate to one” such that in the same circumstances it will do the same thing. But we can easily train a dog in such a way that no one can possibly write down the levers it will choose, since it will be trained to choose the opposite ones.

And still another: a relatively simple robot, programmed in the same way. We don’t need a Laplacian demon, since we can predict ourselves in every circumstance what it will do. But we cannot write that down, since then we would predict the opposite of what we wrote. And it is absolutely irrelevant that the robot is an “instrument,” since the argument does not have any premise saying that human beings are not instruments.

As for the third set, if I understood it correctly you are indeed cherry picking — you are simply selecting the trials where the human made a mistake, and saying, “why did he consistently make a mistake in these cases?” There is no reason; you simply selected those cases.

Chastek responds to this comment in a fairly detailed way. Rather than responding directly to the comment there, I ask him to comment on several scenarios. The first scenario:

If I drop a ball on a table, and I ask you to predict where it is going to first hit the table, and say, “Please predict where it is going to first hit the table, and let me know your prediction by covering the spot with your hand and keeping it there until the trial is over,” is it clear to you that:

a) it will be impossible for you to predict where it is going to first hit in this way, since if you cover a spot it cannot hit there

and

b) this has nothing whatsoever to do with determinism or indeterminism of anything.

The second scenario:

Let’s make up a deterministic universe. It has no human beings, no rocks, nothing but numbers. The wave function of the universe is this: f(x)=x+1, where x is the initial condition and x+1 is the second condition.

We are personally Laplacian demons compared to this universe. We know what the second condition will be for any original condition.

Now give us the option of setting the original condition, and say:

Predict the second condition, and set that as the initial condition. This should lead to a result like (1,1) or (2,2), which contradicts our experience that the result is always higher than the original condition. So the hypothesis that we know the output given the input must be false.

The answer: No. It is not false that we know the output given the input. We know that these do not and cannot match, not because of anything indeterminate, but because the universe is based on the completely deterministic rule that f(x)=x+1, not f(x)=x.

Is it clear:

a) why a Laplacian demon cannot set the original condition to the resulting condition
b) this has nothing to do with anything being indeterminate
c) there is no absurdity in a Laplacian demon for a universe like this

The reason why I presented these questions instead of responding directly to his comments is that his comments are confused, and an understanding of these situations would clear up that confusion. For unclear reasons, Chastek failed to respond to these questions. Nonetheless, I will respond to his detailed comments in the light of the above explanations. Chastek begins:

Here are my responses:

That is impossible… I know what will actually be written, and I know what the person will do. But I also know that those do not and cannot match

But “what will actually be written” is, together with a snapshot of the rest of the universe, an initial condition and “what the person will do” is an outcome. Saying these “can never match” means the demon is saying “the laws of nature do not suffice to go from some this initial condition to one of its outcomes” which is to deny Laplacian demons altogether.

The demon is not saying that the laws of nature do not suffice to go from an initial condition to an outcome. It is saying that “what will actually be written” is part of the initial conditions, and that it is an initial condition that is a determining factor that prevents itself from matching the outcome. In the case of the dropping ball above, covering the spot with your hand is an initial condition, and it absolutely prevents the outcome being that the ball first hits there. In the case of f(x), x is an initial condition, and it prevents the outcome from being x, since it will always be x+1. In the same way, in Chastek’s experiment, what is written is an initial condition which prevents the outcome from being that thing which was written.

If you answer, as you should, that God cannot write what the person will do, but he can know it, the same applies to the Laplacian demon.

When God announces what will happen he can be speaking about what he intends to do, while a LD cannot. I’m also very impressed by John of St. Thomas’s arguments that the world is not only notionally present to God but even physically present within him, which makes for a dimension of his speaking of the future that could never be said of an LD. This is in keeping with the Biblical idea that God not only looks at the world but responds and interacts with it. The character of prophesy is also very different from the thought experiment we’re trying to do with an LD: LD’s are all about what we can predict in advance, but Biblical prophesies do not seem to be overly concerned with what can be predicted in advance, as should be shown from the long history of failed attempts to turn the NT into a predictive tool.

If God says, “the outcome will be A,” and then consistently causes the person to choose A even when the person has hostile intentions, this will be contrary to our experience in the same way that the Laplacian demon would violate our experience if it always got the outcome right. You can respond, “ok, but that’s fine, because we’re admitting that God is a cause, but the Laplacian demon is not supposed to be affecting the outcome.” The problem with the response is that God is supposed to be the cause all of the time, not merely some of the time; so why should he not also say what is going to happen, since he is causing it anyway?

I agree that prophecy in the real world never tells us much detail about the future in fact, and this is verified in all biblical prophecies and in all historical cases such as the statements about the future made by the Fatima visionaries. I also say that even in principle God could not consistently predict in advance a person’s actions, and show him those predictions, without violating his experience of choice, but I say that this is for the reasons given here.

But the point of my objection was not about how prophecy works in the real world. The point was that Catholic doctrine seems to imply that God could, if he wanted, announce what the daily weather is going to be for the next year. It would not bother me personally if this turns out to be completely impossible; but is Chastek prepared to say the same? The real issues with the Laplacian demon are the same: knowing exactly what is going to happen, and to what degree it can announce what it knows.

we can easily train a dog in such a way that no one can possibly write down the levers it will choose, since it will be trained to choose the opposite ones.

Such an animal would follow instructions with some errors, and so would be a fine test subject for my experiment. This is exactly what my subject does in trial #1. I say the same for your robot example.

(ADDED LATER) I’m thankful for this point and developed for reasons given above on the thread.

This seems to indicate the source of the confusion, relative to my examples of covering the place where the ball hits, and the case of the function f(x) = x+1. There is no error rate in these situations: the ball never hits the spot you cover, and f(x) never equals x.

But this is really quite irrelevant. The reason the Laplacian demon says that the experiment is impossible has nothing to do with the error rate, but with the anti-correlation between what is written and the outcome. Consider: suppose in fact you never make a mistake. There is no error rate. Nonetheless, the demon still cannot say what you are going to do, because you always do the opposite of what it says. Likewise, even if the dog never fails to do what it was trained to do, it is impossible for the Laplacian demon to say what it is going to do, since it always does the opposite. The same is true for the robot. In other words, my examples show the reason why the experiment is impossible, without implying that a Laplacian demon is impossible.

We can easily reconstruct my examples to contain an error rate, and nonetheless prediction will be impossible for the same reasons, without implying that anything is indeterminate. For example:

Suppose that the world is such that every tenth time you try to cover a spot, your hand slips off and stops blocking it. I specify every tenth time to show that determinism has nothing to do with this: the setup is completely determinate. In this situation, you are able to indicate the spot where the ball will hit every tenth time, but no more often than that.

Likewise suppose we have f(x) = x+1, with one exception such that f(5) = 5. If we then ask the Laplacian demon (namely ourselves) to provide five x such that the output equals the input, we will not be able to do it in five cases, but we will be able to do it in one. Since this universe (the functional universe) is utterly deterministic, the fact that we cannot present five such cases does not indicate something indeterminate. It just indicates a determinate fact about how the function universe works.

As for the third set, if I understood it correctly you are indeed cherry picking — you are simply selecting the trials where the human made a mistake,

LD’s can’t be mistaken. If they foresee outcome O from initial conditions C, then no mistake can fail to make O come about. But this isn’t my main point, which is simply to repeat what I said to David: cherry picking requires disregarding evidence that goes against your conclusion, but the times when the random number generator and the LD disagree provide no evidence whether LD’s are consistent with our experience of following instructions with some errors.

I said “if I understood it correctly” because the situation was not clearly laid out. I understood the setup to be this: the Laplacian demon writes out fifty letters, A or B, being the letters it sees that I am going to write. It does not show me this series of letters. Instead, a random process outputs a series of letters, A or B, and each time I try to select the opposite letter.

Given this setup, what the Laplacian demon writes always matches what I select. And most of the time, both are the opposite of what was output by the random process. But occasionally I make a mistake, that is, I fail to select the opposite letter, and choose the same letter that the random process chose. In these cases, since the Laplacian demon still knew what was going to happen, the demon’s letter also matches the random process letter, and my letter.

Now, Chastek says, consider only the cases where the demon’s letter is the same as the random process letter. It will turn out that over those cases, I have a 100% failure rate: that is, in every such case I selected the same letter as the random process. According to him, we should consider this surprising, since we would not normally have a 100% failure rate. This is not cherry picking, he says, because “the times when the random number generator and the LD disagree provide no evidence whether LD’s are consistent with our experience of following instructions with some errors.”

The problem with this should be obvious. Let us consider demon #2: he looks at what the person writes, and then writes down the same thing. Is this demon possible? There will be some cases where demon #2 writes down the opposite of what the random process output: those will be the cases where the person did not make a mistake. But there will be other cases where the person makes a mistake. In those cases, what the person writes, and what demon #2 writes, will match the output of the random process. Consider only those cases. The person has a 100% failure rate in those cases. The cases where the random process and demon #2 disagree provide no evidence whether demon #2 is consistent with our experience, so this is not cherry picking. Now it is contrary to our experience to have a 100% failure rate. So demon #2 is impossible.

This result is of course absurd – demon#2 is obviously entirely possible, since otherwise making copies of things would be impossible. This is sufficient to establish that Chastek’s response is mistaken. He is indeed cherry picking: he simply selected the cases where the human made a mistake, and noted that there was a 100% failure rate in those cases.

In other words, we do not need a formal answer to Chastek’s objection to see that there is something very wrong with it; but the formal answer is that the cases where the demon disagrees with the random process do indeed provide some evidence. They question is whether the existence of the demon is consistent with “our experience of following instructions with some errors.” But we cannot have this experience without sometimes following the instructions correctly; being right is part of this experience, just like being wrong. And the cases where the demon disagrees with the random process are cases where we follow the instructions correctly, and such cases provide evidence that the demon is possible.

Chastek provides an additional comment about the case of the dog:

Just a note, one point I am thankful to EU for is the idea that a trained dog might be a good test subject too. If this is right, then the recursive loop might not be from intelligence as such but the intrinsic indeterminism of nature, which we find in one way through (what Aristotle called) matter being present in the initial conditions and the working of the laws and in another through intelligence. But space is opened for one with the allowing of the other, since on either account nature has to allow for teleology.

I was pointing to St. Thomas in my response with the hope that St. Thomas’s position would at least be seen as reasonable; and there is no question that St. Thomas believes that there is no indeterminism whatsoever in the behavior of a dog. If a dog is in the same situation, he believes, it will do exactly the same thing. In any case, Chastek does not address this, so I will not try at this time to establish the fact of St. Thomas’s position.

The main point is that, as we have already shown, the reason it is impossible to predict what the dog will do has nothing to do with indeterminism, since such prediction is impossible even if the dog is infallible, and remains impossible even if the dog has a deterministic error rate.

The comment, “But space is opened for one with the allowing of the other, since on either account nature has to allow for teleology,” may indicate why Chastek is so insistent in his error: in his opinion, if nature is deterministic, teleology is impossible. This is a mistake much like Robin Hanson’s mistake explained in the previous post. But again I will leave this for later consideration.

I will address one last comment:

I agree the physical determinist’s equation can’t be satisfied for all values, and that what makes it possible is the presence of a sort of recursion. But in the context of the experiment this means that the letter on a sheet of paper together with a snapshot of the rest of the universe can never be an initial condition, but I see no reason why this would be the case. Even if I granted their claim that there was some recursive contradiction, it does not arise merely because the letter is given in advance, since the LD could print out the letter in advance just fine if the initial conditions were, say, a test particle flying though empty space toward button A with enough force to push it.

It is true that the contradiction does not arise just because the Laplacian demon writes down the letter. There is no contradiction even in the human case, if the demon does not show it to the human. Nor does anything contrary to our experience happen in such a case. The case which is contrary to our experience is when the demon shows the letter to the person; and this is indeed impossible on account of a recursive contradiction, not because the demon is impossible.

Consider the case of the test particle flying towards button A: it is not a problem for the demon to write down the outcome precisely because what is written has no particular influence, in this case, on the outcome.

But if “writing the letter” means covering the button, as in our example of covering the spot where the ball will hit, then the demon will not be able to write the outcome in advance. And obviously this will not mean there is any indeterminism.

The contradiction comes about because covering the button prevents the button from being pushed. And the contradiction comes about in the human case in exactly the same way: writing a letter causes, via the human’s intention to follow the instructions, the opposite outcome. Again indeterminism has nothing to do with this: the same thing will happen if the human is infallible, or if the human has an error rate which has deterministic causes.

“This means that the letter on a sheet of paper together with a snapshot of the rest of the universe can never be an initial condition.” No, it means that in some of the cases, namely those where the human will be successful in following instructions, the letter with the rest of the universe cannot be an initial condition where the outcome is the same as what is written. While there should be no need to repeat the reasons for this at this point, the reason is that “what is written” is a cause of the opposite outcome, and whether that causality is deterministic or indeterministic has nothing to do with the impossibility. The letter can indeed be an initial condition: but it is an initial condition where the outcome is the opposite of the letter, and the demon knows all this.

Composing Elements

Suppose we have two elements, as for example water and earth (not that these are really elements.) How do we make something out of the elements? We can consider two different possible ways that this could happen.

Suppose that when we combine one part water and one part earth, we get mud, and when we combine one part water and two parts earth, we get clay. Thus clay and mud are two different composite bodies that can be made from our elements.

How do we expect clay and mud to behave? We saw earlier that the nature of the physical world more or less requires the existence of mathematical laws of nature. Now we could say, “Clay and mud are made of earth and water, and we know the laws governing earth and water. So we can figure out the behavior of clay and mud using the laws governing earth and water.”

But we could also say, “Although clay and mud are made of earth and water, they are also something new. Consequently we can work out the laws governing them by experience, but we cannot expect to work them out just from the laws governing earth and water.”

These two claims are basically opposed to one another, and we should not expect that both would be true, at least in any particular instance. It might be that one is true in some cases and the other is true in some cases, or it might be that one side is always true. But in any case one will be true and not the other, in each particular situation.

Someone might argue that the first claim must be always true in principle. If water behaves one way by itself, and another way when it is combined with earth, then you haven’t sufficiently specified the behavior of water without including how it behaves when it is beside earth, or mixed with earth, or combined in whatever way. So once you have completely specified the behavior of water, you have specified how it behaves when combined with other things.

But this way of thinking is artificial. If water follows an inverse square law of gravity by itself, but an entirely different mathematical law when it is combined with earth, rather than saying that the entirely different law is a special case governing water, we should just admit that the different law is a law governing clay and mud, but not water. On the other hand, it is not unreasonable to include various potential interactions in your laws governing water, rather than only considering how water behaves in perfect isolation. Thus for example one would want to say that water suffers gravitational effects from all other bodies, rather than simply saying that water attracts itself. Nonetheless, even if the distinction is somewhat rough, there is a meaningful distinction between situations where the laws governing the elements also govern the composites, and situations where we need new laws for the composites.

In one way, the second claim is always true. It is always the case that something is true of the composite which is not true of the elements in themselves, since the composite is a whole composed of elements, while the elements in themselves are not. This is true even in artificial compositions; the parts of a bicycle are not a bicycle, but the whole is. And I can ride a bicycle, but  I cannot ride the individual pieces of metal that form it. Likewise, it is evidently true of living things, which are alive, and in some cases have conscious experience, even though the individual elements do not.

In a second way, the second claim is almost always true. If we consider our laws as practical methods for predicting the behavior of a physical system, in practice we will almost always need special laws to predict the behavior of a complex composite, if only because it would be too complex and time consuming to predict the behavior of the composite using laws governing only the parts. Thus people who wish to predict the weather use generalizations based on the experience of weather, rather than trying to predict the weather simply by considering more general laws of physics, despite believing that the weather is in fact a consequence of such general laws.

In a third way, the first claim is true at least frequently, and possibly always. If we consider the behavior of a bicycle or a computer, not with respect to general questions such as “can I ride it?” or “can it calculate the square root of two?”, but with respect to the physical movement of the parts, there are good reasons to think that the behavior of the whole can be determined from the behavior of the parts of which it is composed. For these are human inventions, and although experience is involved in such inventions, people make guesses about new behavior largely from their understanding of how the parts behave which they plan to put together. So if the whole behaved in ways which are significantly unpredictable from the behavior of the parts, we would not expect such inventions to work. Likewise, as said above, there is little reason to doubt that the weather results from general principles of physics that apply to earth, air, water, and so on.

I say “possibly always” above, because there is no case where the second claim is known to be true in this sense, and many instances, as noted, where the first is known or reasonably believed to be the case. Additionally, one can give reasons in principle for expecting the first claim to be true in this way, although this is a matter for later consideration.

An important objection to this possibility is that the fact that the second claim is always true in the first way mentioned above, seems to imply that the first claim cannot be true even in the third way, at least in some cases. In particular, the conscious behavior of living things, and especially human free will, might seem inconsistent with the idea that the physical behavior of living things is in principle predictable from laws governing their elements.

Will and Experience

Just as we learn the nature of desire from experience, so we also learn from experience the effectiveness of some desires. Thus for example if I want to move my hand, I move my hand. On the other hand, if I want the lamp on my desk to pass to the other side of the room, it does not do so in the way that my hand moves when I want that to happen. Or if I am inside the house and want to be outside, I do not simply pass through the walls, but I need to perform a particular series of actions such as walking to the door and opening it.

All of these are simple facts about the world that we learn from experience, long before any philosophical reflection. But they are facts about the way the world works, not self evident consequences of the nature of our will or desire. I cannot rearrange the stars simply by willing it, but there is no reason in principle why I would find it strange if I could; it is merely a fact of experience that moving the stars is not in my power.

Likewise, there are some things where I do have some immediate ability to do what I wish, but not a perfect ability. For example, I can choose to draw a circle, but the circle is not perfect. And the circle would have been even less perfect in the past, before I had some experience of drawing. So my ability in this case can be improved by practice.

In a similar way, by the use of biofeedback, people can sometimes learn to change their body in various ways that one cannot normally control. Naturally, there are limits to this technique; no one will use it to obtain power over the movement of the stars.

 

Causality and Free Will

We have argued that there is a first efficient cause, and that there is only one such cause. It follows that nothing can escape the causality of this cause, not even things that we would usually think of as caused by chance or by free will.

It is clear from experience that human beings make choices. However, whatever we might say about our freedom in these choices, we cannot avoid admitting that the first cause not only causes us to exist, but also to make the choices that we make. St. Thomas describes this situation:

The divine will imposes necessity on some things willed but not on all. The reason of this some have chosen to assign to intermediate causes, holding that what God produces by necessary causes is necessary; and what He produces by contingent causes contingent. This does not seem to be a sufficient explanation, for two reasons.

First, because the effect of a first cause is contingent on account of the secondary cause, from the fact that the effect of the first cause is hindered by deficiency in the second cause, as the sun’s power is hindered by a defect in the plant. But no defect of a secondary cause can hinder God’s will from producing its effect.

Secondly, because if the distinction between the contingent and the necessary is to be referred only to secondary causes, this must be independent of the divine intention and will; which is inadmissible. It is better therefore to say that this happens on account of the efficacy of the divine will. For when a cause is efficacious to act, the effect follows upon the cause, not only as to the thing done, but also as to its manner of being done or of being. Thus from defect of active power in the seed it may happen that a child is born unlike its father in accidental points, that belong to its manner of being. Since then the divine will is perfectly efficacious, it follows not only that things are done, which God wills to be done, but also that they are done in the way that He wills. Now God wills some things to be done necessarily, some contingently, to the right ordering of things, for the building up of the universe. Therefore to some effects He has attached necessary causes, that cannot fail; but to others defectible and contingent causes, from which arise contingent effects. Hence it is not because the proximate causes are contingent that the effects willed by God happen contingently, but because God prepared contingent causes for them, it being His will that they should happen contingently.

We could compare this situation to the situation of an author with respect to the imaginary world that he creates. Thus I can write the following story:

Peter Smith was out for a walk with Michael Jones. They came to a fork in the path. Peter, having the freedom to go to the left or to the right, freely chose to go to the right. Michael, however, was under the mental influence of aliens and had no choice in the matter. They compelled him to go to the left, and so he and Peter parted ways.

Note that in this story, Peter is free and Michael is not. And this happens because I decided that it was going to happen that way. Since I am responsible for whole of their imaginary existence, I am also responsible for the fact that one of them has an imaginary free existence, and one does not. In the same way, the first cause is responsible not only for the things that exist, but for everything which is true about the things that exist, including whatever kind of freedom or contingency that they might possess.