When we say that John caused the movement of his arm, what do we really mean? Presumably, John’s decision to move the arm is caused by the laws underpinning his brain. Either these laws are indeterministic if quantum mechanics in its current state is complete or is deterministic if there’s a deterministic theory that more completely defines reality.

Either way, the causal chain would brutely start at these laws, not John himself. Where, then, does John enter the causal picture?

Perhaps one may object to this and say that because the arm belongs to John, or because the law is working upon John, John is still causing it.

But noone says, for example, that an apple falling down from a tree is caused by the apple. We understand that the laws underpinning the movement of the apple such as gravity cause the apple to fall down. Why not the same for John?

If this is true, then it seems to imply that mental causation, regardless of the nature of reality being deterministic or not, cannot exist. This would have massive consequences not just in the human level but also on a God level if He exists. Does this imply that all causal chains must begin with a mindless cause?

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    Where does John enter...? The arm is John's arm the brain is John's brain... Commented Dec 11, 2023 at 11:55
  • @MauroALLEGRANZA I already addressed this. The apple stalk is part of the apple. Does the apple cause the apple stalk to fall down from a tree?
    – user62907
    Commented Dec 11, 2023 at 11:59
  • much depends on John/*when* we say/what you really mean...but no, your implication is wrong. only one (or many) wrong "cause" doesn't make all "causes" wrong/mindless/senseless ..you'd really have to prove it for "all" ...
    – xerx593
    Commented Dec 11, 2023 at 12:19
  • (assume) someone/-thing caused john's arm/the apple to move, so there must (have) be(en) a "cause", but making it "John" or "the apple" is probably mindless. (the one is a "fictive person name", the other "a piece of frui.) ..reg. "non-deterministic": for me (as a "computer scientist") just means: when there was one cause, there could also have been two (or multiple, independent) "reasons". regarding "ultimate cause mindless", if it was like that, then words like "cause", or "reason" (or "good","bad","sky", earth","sense","mind".even "mindless"...all words) would have NO SENSE, would they?
    – xerx593
    Commented Dec 11, 2023 at 12:35
  • ..and (reg. ND vs D) while "john maybe (consciously or intuitively) causes his arm to move a few 'inches'", the "earth rotation" moves it a few thousand miles.. which is also outnumbered by "solar" and "galactic movement" ...so john can (consciously or intuitively) cause all his movements (on his "scale", "forge his fate"), but he cannot(?) cause solar, galactic, or even the movement of his "biome"... (i think:) similar to "quant vs particle" (a.s.o.)
    – xerx593
    Commented Dec 11, 2023 at 12:51

8 Answers 8


Either way, the causal chain would brutely start at these laws, not John himself. Where, then, does John enter the causal picture?

Your question is arguably the central question of Compatibilism, and there's no universally satisfying answer, but the answer I've been leaning towards over the last couple years is that Emergence allows us to talk about different layers of causality.

It's true that John lifted his arm because he wanted to lift his arm.

It's also true that every fundamental particle in John's body was, the whole time, behaving exactly like those sub-atomic particles should behave, according to the laws of physics.

The idea of Emergence-centered compatibilism is that you have to have a way for those both to be true at the same time - that John and his mind are causal, but that they're not causal over and above the laws of physics underpinning his physical body and brain. Simultaneous layers of causality that apply at different scales of looking at reality.


John's decision to move his arm changes the configuration of his motor cortex neurons causing them to send the intended control signals to his muscles.

This is the point where mental causation happens. All his thoughts and ideas are encoded (~written) in the brain cells and that includes also ideas about moving his muscles.

John's decision is the cause starting a new causal chain of consequences. A decision is a mental thing that cannot be caused.

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    @thinkingman John makes the decision that causes the action. Commented Dec 11, 2023 at 12:33
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    @thinkingman Decisions are not caused, only physical events are caused. John does not "cause" the decision, he makes it. John decides. Commented Dec 11, 2023 at 13:22
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    @PerttiRuismäki To state "John makes the decision" cannot be the answer. - How does John make the decision, the underlying mechanism has to be explained. This seems to me the proper problem behind the OP's question.
    – Jo Wehler
    Commented Dec 11, 2023 at 21:40
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    "A decision is a mental thing that cannot be caused." Arguably, every decision is caused by two things (at once): 1. The prior history that has shaped the neural structure to be what it is. 2. An external stimulus is received. It being a decision only implies that the response to the stimulus was not random or instinctual but analytical (to an extent).
    – rus9384
    Commented Dec 11, 2023 at 21:54
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    So you're asserting that John's decision is not caused by physical processes? I take it you're a dualist? And you're simply asserting dualism as a fact without any support? Commented Dec 12, 2023 at 5:20

Where, then, does John enter the causal picture?

As @MauroALLEGRANZA points out, the whole process operates within John. Hence the more precise question must be: Where inside John does the process start?

To simplify the question one can leave quantum mechanics aside. According to present knowledge, the indeterminism of quantum mechanics is not relevant for the combined action of a net of neurons, operating in the thermic environment of the living brain.

  1. A scientific explanation can only rely on our knowledge from neuroscience, the wiring of the neurons and the mechanism of the synapses. The end of the process, which starts the bodily action, is well known: Electric stimuli in a certain areal of the cortex. The open question:

    Which events trigger the mental processes which in the end trigger the motor areal?

    At least since Libet’s investigation of the readiness potential it is clear: These processes originate as unconscious mental processes. Therefore it were not a scientific explanation to consider the mind - taken as a philosophical entity separated from the bodily brain – to be the first cause.

    Because the first cause are our unconsciuos mental processes, we have no direct access to the cause via introspection. Of course we have the subjective experience of being the actor and often we feel as the decision maker. But we cannot identify in which part of our brain the process starts.

    As long as we live, our brain is active. Therefore the causes of a specific action are

    • on one hand, a subset of the totality of our mental processes, in particular the memory processes,

    • and on the other hand, the neuronal processes due to specific exterior triggers from our sense organs.

  2. Kant stated that humans have the capability to start new causal chains out of freedom. This statement is neither supported by neuroscience, nor does it show a scientific approach to solve the problem of free will, voluntary action and human agency.


The difference is that you can treat the apple as a blackbox (and to some extend we do that already). That is you take the thing hanging at the tree and assign it a label and describe it by it's physical properties. For example in case of the apple it's its weight, bonding to the tree and whatnot.

Then if you know the force that the environment puts on the apple and you know the strength with which it binds to the tree and can calculate what the apple will do next. There's no knowledge required about the inner workings of that apple for all intents and purposes it could be just a paperweight with comparable physical properties.

And now compare that to John. Sure you can estimate that if you subject John to a tornado that he'll behave like a rag doll and similarly behaves like an object, but let's tune the wind a little and let's say I give you all the parameters that you want about John's environment, can you predict how John will react?

And as of right now the answer is no. Whether John will raise or lower his arm is not a function of the environment (at least not in the sense of a direct cause and effect like for the apple), but it is a functionality that happens inside that object labeled John. So for all intents and purposes "John is doing it".

Now that opens up a whole host of new questions like "what even is john" and "where inside john is the john that is doing it". But nonetheless you can argue that it's a property of the blackbox named John, rather than of the environment.

Sure deep down it could be, and likely is, that the environment changes the configuration of some inner states within John so that the result is... and so on. But unless you can follow the chain of events it's a valid short hand to refer to the situation as John doing something, isn't it?

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    It seems that all you’re arguing for is the usefulness of stating that John causes X. But the question is about what’s really going on. And underneath this abstraction, you seem to agree with me that what’s happening internal to John is still completely influenced by laws that aren’t caused by John.
    – user62907
    Commented Dec 11, 2023 at 12:17
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    @thinkingman We don't know what is really going on, that is why people still speculate about that. However what we see is that the motion of the blackbox called "apple" can be described by just knowing external variables, while the blackbox called "John" behaves erratic, save for extreme cases where it breaks and turns into an object. We suspect that what's happening in John is subject to the same laws of physics that we apply elsewhere (why not...) and that is actually true for the dead matter making up the blackbox containing John, however the living John is a much harder enigma.
    – haxor789
    Commented Dec 11, 2023 at 12:30

There is not a solid deductive inference from, "The causes of human behavior precede human mental activity," to, "All effects have causes that precede mental activity." Among other things, if panpsychism were unrestrictedly true, then every causal entity would have a mind anyway. Now, as for the divine nature, this thing has no brain, nor even really a mind like humans do; attributing a mind to It is an act of analogy. So even an inductive inference involving the behavior of material composites and epiphenomenalism about their minds would not likely transfer over to the divine nature.

Also, do laws themselves cause anything, and if so in what sense? We might assume that a law is an immortal proposition in a priori space, imposing itself on the otherwise-chaos of empirical events, fixing how they unfold. This would be something of a Platonistic picture of laws. Or perhaps laws are primarily internal to their objects; this would be more Aristotelian a gloss of the situation. But so in the latter event(!), we should have cause(!) to look into e.g. new mechanism: rather than universally quantified propositions determining particulars by specification, we would have existentially quantified propositions expressing the natures of particulars unto generalization.

We should also be minded(!) not to necessarily identify human free will with causality within the empirical world almost at all. Kant held that physical behavior as such could be fully explained in-world by causal chains, but that when we pass to moral reason and understanding, we look outside those chains, into "another" world (or level of reality), and things look different, there. With the category of cause-and-effect no longer applying in much the same way as it does when we engage in physical judgments, then, we see in moral judgment that there is an alternative application of the category, again analogical we might say, lending itself to distinct conclusions about contingency and necessity, here.


We cannot determine the character of an ultimate source of cause because we apprehend causes with our conscious mind in the context of drama. Drama is what Spinoza calls an affect or emotion: a feeling of desire, pleasure, or pain accompanied by an idea of its cause. Asking if an ultimate cause is mindless arises in the context of drama which is an operation of the conscious mind. Mind and not-mind, conscious and unconscious, are distinctions in the conscious mind.

The Unconscious is a paradox - Helmholtz laid the foundation for Freud's invention of the unconscious as a source of cause of ego dysfunction. Freud argues that the conscious mind is healthy when the ego, the effort to govern action in the sensory context, becomes prudent, which is the ability to govern action by the use of reason. Freud said desires and the biological id (inner drives) send impulses to the ego which can be activated or inhibited in the sensory context. The impulses arrive from the unconscious, cross a threshold, and become conscious to the ego (Spinoza describes desire as appetite accompanied by consciousness thereof but Freud gives no credit to Spinoza). So the ego lacks prudence when the unconscious biological impulses or personal memories interfere with the operation of the prudent ego in the present. Beyond that Freud injects his own residual unconscious infantile drama into every human interaction that he calls psychoanalysis.

Helmholtz argues that our sense-perceptions are products of an unconscious process that transforms sensory responses to stimuli into perceptions in our conscious mind. Since we do not make all the conscious inferences necessary to perceive the moon, for example, as larger than our thumb, he maps these inferences to the unconscious, and describes the perception as the product of a process called unconscious inference. Hold your thumb up to the moon it will obscure the full moon. So in the field of raw visual perception the thumb is bigger than the moon. But in the field of three-dimensional perceptions the moon is large and far away. All these words and concepts arise only in the conscious mind. How can the conscious mind ever know whether the unconscious process has the exclusive character of the mind of of the mindless? The distinction between mind and mindless occurs in the mind!

Spinoza says the mind cannot determine the body to act nor can the body determine the mind to think. Thought and action are like two sides of one coin. I once heard a psychologist state, "It is not enough to pray - you have to take action!" This caused me the think, "Action is Prayer! Prayer is Action!" Most humans act impulsively not knowing that their action is a prayer to obtain some outcome and those who pray have an inner form of action somewhat independent of the sensory context!


"Ultimate cause" sounds rather religious, so I will ignore that, and focus on "cause". In physics there is supposedly no such thing as an ultimate cause.

We can imagine an experiment during which John is instructed to raise his arm if and only if asked to do so by someone else, called Mary. John agrees with the experiment, and he raises his arm when Mary tells him: "raise your arm" or "put your arm up, please", or any sentence with a similar meaning.

In this sequence of events, the order given by Mary, expressed in symbolic language and most probably mindful, acts as a cause for John's movement.

Similarly, you could ask yourself whether the cause of your OP is mindful. And if it is not, does your OP belong here on PSE? Does it qualify as philosophy if it does not originate from some mindful place?


Quantum Physics has two views of "cause", in the first cause lies in the succession of states leading up to an event involving isolated, single particles, in the second it is due to decoherence of one entangled set of objects by another entangled set of physical objects.

The single particle is a special case of the more general, second type of cause by decoherence.

Most decoherence is due to the environment. Decoherence involves the selection of states that are the most likely fit when the mutually entangled environment meets a hitherto isolated object. The evolution of a quantum system can then be seen as a growth of the state of the environment over time. Causation becomes a result of the form of large objects (the layout of the environment in space and time). It is a process of accretion onto a template provided by a pre-existing form.

I think that quantum physics is telling us that events are in the future until they happen. This is an obvious truism but most of us regard cause and effect as past events providing a sort of nudge through time when a clearer view might be that past events create a form that can create and receive an event.

If we take the path of an isolated electron Feynman's proposal applies: "The electron explores all worldlines between source and detector." The environment provides the form of the emitter and detector for the electron. The path of the electron that we observe is due to the interference of all possible paths.

The principle of least action summarises the interference between all possible paths and provides a classical description of the path of particles which, for large objects, looks like determinism. See https://www.eftaylor.com/pub/ActionSummary.pdf Feynman's theory is now fairly mainstream physics.

If we consider ourselves moving through the environment then we also explore all possible paths (possible futures for us) but are so rapidly decohered by the environment that the paths are of effectively no length. However, the possible futures are the future coming to meet us, even if it is predictable from second to second.

If time exists as a direction for arranging events then quantum physics offers an escape from a block universe. Tiny deviations from classical predictions may give rise to large deviations as they interact with the environment.

The only way that I can see for us to escape determinism is if we are sensitive to some special event in our brains that remains coherent (obeys schrodinger' equation) for seconds and is not snuffed out immediately by interactions. Calculations show the decoherence time scales for most objects in the brain are really short (10^-20 seconds https://journals.aps.org/pre/abstract/10.1103/PhysRevE.61.4194 ) so any special source of coherence would need to be something novel in the brain that escapes interactions for extended periods.

See https://drsimonrobin.substack.com/p/chapter-6-the-mind for further discussion.

  • How can there be future events? This is impossible. There are memories of past events and events in the present which a conscious observer infers will give rise to similar events in the future. In reality all events occur NOW. This is not stated to dispense with scientific ideas of time but rather to comprehend how the mind generates the concept of an event in the context of science. Reality has attributes of the eternal NOW. Commented Dec 11, 2023 at 22:13
  • How can we have events in the present? How much of a word is "now"? Presentism has more serious problems than 4 dimensionalism. Commented Dec 12, 2023 at 14:20
  • All (quantum) events that are happening NOW must be simultaneous and all quantum events that are not happening NOW do not exist as quantum events. But the local observer cannot register all events happening NOW. Humans infer that some quantum event from the past caused the observed quantum events happening NOW (with propogation delay). This means the past is the inference of the observer not a global map of space-time. See this video on simultaneous events: youtu.be/894ZI68rdys. The universe or reality is not generating future or past quantum or macroscopic events in the eternal NOW. Commented Dec 12, 2023 at 16:38
  • The NOW is the plane of simultaneity of the observer. If what you say about quantum events only existing NOW were true then an oscillating electron wipes out all quantum events cyclically. Commented Dec 13, 2023 at 15:29
  • The models we have for simple harmonic oscillation are sinusoidal waveforms that repeat in sequence. Individual points on the waveform are timeless whereas any finite segment of the waveform represents elapsed time. Each point occurs NOW the waveform is derived from our conceptual faculties and the memories of the changing states in the past. Reality does appear to be based on this principle of resonance which is always present in the NOW or else we would not be able to build physical models for relativity, space, and time. Oscillators do not contradict the observation of events and memories. Commented Dec 13, 2023 at 17:12

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