Many times on this site, I’ve come across the argument (usually related to free will and/or consciousness) that either everything is determined, or everything is random. Often, each of these options is identified with classical physics (in the case of determinism) or quantum physics (in the case of randomness). Those who hold this position assert that everything we think, feel, believe, etc., is determined because it is governed by the “determinism” of classical physics and, to the extent that quantum physics allows indeterminism into the picture it is irrelevant, because it is just random: “quantum consciousness” can’t entail free will because we are then governed by randomness, not “will”.
This view is wrong. It is not just wrong because it mistakes the nature of both classical dynamics and quantum physics. It is wrong because it mistakes the nature of causality (opting for the simplistic models in vogue thousands of years ago). It is wrong because it misunderstands the nature of randomness. It is wrong because it mistakes our understanding of living systems. Basically, it is wrong.
But simple assertions mean nothing. So I will start by explaining the difference between the nature of “randomness” in quantum mechanics and that which is behind the belief that indeterministic (“random”) processes couldn’t be relevant to free will.
Randomness of the type that is necessarily irrelevant to free will is akin to Brownian motion. Lots of interacting “parts” of some system (like gas molecules or dust particles) bounce of each other. There is no rhyme or reason, no pattern, no organization, nothing other than an enormous set of possible outcomes given particular initial conditions. Also, if we let a system governed by Brownian motion “run” for a while and then observe its state, what we find is “random” in that it is neither predictable nor special: lots of similar possible outcomes could have occurred given slight variations. That’s “random”.
In quantum physics, outcomes are “random” because we cannot, even in principle, know what the outcome will be. That’s because it isn’t determined by any set of complex interactions (as in the case of Brownian motion) that are too numerous for us to deal with in order to predict. The unpredictability is “built in”. And this is what makes it not “random” in the sense we are familiar with. True, randomness always entails something about our limited powers of prediction. Usually, however, this is because of our measurement limitations and/or computational limitations. In quantum physics, outcomes are not random (if they were random, the quantum theories, from QM to the standard model, would be useless). Systems in particular states have a particular set of possible future states, and the reason quantum physics is successful is because we can predict with certain known probabilities what these future states will be. What we can’t know is what “determines” which state we will find. But we do know that we can ensure some set of particular outcomes if we observe systems in particular ways (e.g., we can determine whether we will see electrons or photons as wave-like or particle-like). It is entirely possible that quantum effects in the brain are “unpredictable” because the possible outcomes are determined by the brain itself. In fact, the free will theorem proves that there is a certain degree of free will (in a limited sense) in everything by virtue largely of this “quantum randomness”. The point is that this “randomness” doesn’t mean the kind of random, chaotic set of possible outcomes we associate with randomness, just that we cannot know how outcomes could, even in principle, be determined.
Then there is the problem with the deterministic view of classical physics. Newtonian mechanics is deterministic. It also fails even in classical physics. So does determinism. This is because classical determinism subscribes to a view of causation in which every effect has some necessary and sufficient set of causes which uniquely and solely determine it. In reality, this is bogus. Higher level structures (neural activity, cellular metabolism, social dynamics, swarm behavior, etc.) determine lower level dynamics. Sometimes this simply means that we can create a causal model but that it is arbitrary. This is often true of simple feedback: changes in x result in changes in y, but changes in y result in changes in x, and the only way to determine whether changes in x cause changes in y or vice versa is by arbitrary decision. Then there is the acausal nature of phenomena like motion in general relativity: matter moves because spacetime curves, but spacetime curves because of matter. Both happen simultaneously. Finally (at least as far as my examples go) there is nonlinear or circular causality of the type exhibited with functional emergence. Consider a model of a cell. Perhaps the most important function is metabolism. Most of the time, most of cellular dynamics consists metabolic activity. So metabolism is a function of the activity of most of the cell most of the time. Yet what determines the dynamics of the parts of the cell? Metabolism. It’s circular, and we can’t even arbitrarily choose causes in order to separate out effects vs. causes even arbitrarily.
So this dichotomous causal model is simply wrong no matter how we look at it. It assumes a linear view of time which doesn’t exist in relativistic physics (including quantum physics). It assumes the kind of linear phenomena that for the most part exist only as idealizations and aren’t exhibited by natural systems. It is inconsistent with nonlocality. It assumes the reductive view of Newtonian mechanics which was never shown to hold true in general, contradicts our experience, and now contradicts mainstream physics itself. It explains nothing, but fails to explain the more important phenomena in our experiences and arguably within science (particularly given the importance of the observer in quantum physics): that of consciousness.
Why do so many seem to hold on to an outdated causal model?
This view is wrong. It is not just wrong because it mistakes the nature of both classical dynamics and quantum physics. It is wrong because it mistakes the nature of causality (opting for the simplistic models in vogue thousands of years ago). It is wrong because it misunderstands the nature of randomness. It is wrong because it mistakes our understanding of living systems. Basically, it is wrong.
But simple assertions mean nothing. So I will start by explaining the difference between the nature of “randomness” in quantum mechanics and that which is behind the belief that indeterministic (“random”) processes couldn’t be relevant to free will.
Randomness of the type that is necessarily irrelevant to free will is akin to Brownian motion. Lots of interacting “parts” of some system (like gas molecules or dust particles) bounce of each other. There is no rhyme or reason, no pattern, no organization, nothing other than an enormous set of possible outcomes given particular initial conditions. Also, if we let a system governed by Brownian motion “run” for a while and then observe its state, what we find is “random” in that it is neither predictable nor special: lots of similar possible outcomes could have occurred given slight variations. That’s “random”.
In quantum physics, outcomes are “random” because we cannot, even in principle, know what the outcome will be. That’s because it isn’t determined by any set of complex interactions (as in the case of Brownian motion) that are too numerous for us to deal with in order to predict. The unpredictability is “built in”. And this is what makes it not “random” in the sense we are familiar with. True, randomness always entails something about our limited powers of prediction. Usually, however, this is because of our measurement limitations and/or computational limitations. In quantum physics, outcomes are not random (if they were random, the quantum theories, from QM to the standard model, would be useless). Systems in particular states have a particular set of possible future states, and the reason quantum physics is successful is because we can predict with certain known probabilities what these future states will be. What we can’t know is what “determines” which state we will find. But we do know that we can ensure some set of particular outcomes if we observe systems in particular ways (e.g., we can determine whether we will see electrons or photons as wave-like or particle-like). It is entirely possible that quantum effects in the brain are “unpredictable” because the possible outcomes are determined by the brain itself. In fact, the free will theorem proves that there is a certain degree of free will (in a limited sense) in everything by virtue largely of this “quantum randomness”. The point is that this “randomness” doesn’t mean the kind of random, chaotic set of possible outcomes we associate with randomness, just that we cannot know how outcomes could, even in principle, be determined.
Then there is the problem with the deterministic view of classical physics. Newtonian mechanics is deterministic. It also fails even in classical physics. So does determinism. This is because classical determinism subscribes to a view of causation in which every effect has some necessary and sufficient set of causes which uniquely and solely determine it. In reality, this is bogus. Higher level structures (neural activity, cellular metabolism, social dynamics, swarm behavior, etc.) determine lower level dynamics. Sometimes this simply means that we can create a causal model but that it is arbitrary. This is often true of simple feedback: changes in x result in changes in y, but changes in y result in changes in x, and the only way to determine whether changes in x cause changes in y or vice versa is by arbitrary decision. Then there is the acausal nature of phenomena like motion in general relativity: matter moves because spacetime curves, but spacetime curves because of matter. Both happen simultaneously. Finally (at least as far as my examples go) there is nonlinear or circular causality of the type exhibited with functional emergence. Consider a model of a cell. Perhaps the most important function is metabolism. Most of the time, most of cellular dynamics consists metabolic activity. So metabolism is a function of the activity of most of the cell most of the time. Yet what determines the dynamics of the parts of the cell? Metabolism. It’s circular, and we can’t even arbitrarily choose causes in order to separate out effects vs. causes even arbitrarily.
So this dichotomous causal model is simply wrong no matter how we look at it. It assumes a linear view of time which doesn’t exist in relativistic physics (including quantum physics). It assumes the kind of linear phenomena that for the most part exist only as idealizations and aren’t exhibited by natural systems. It is inconsistent with nonlocality. It assumes the reductive view of Newtonian mechanics which was never shown to hold true in general, contradicts our experience, and now contradicts mainstream physics itself. It explains nothing, but fails to explain the more important phenomena in our experiences and arguably within science (particularly given the importance of the observer in quantum physics): that of consciousness.
Why do so many seem to hold on to an outdated causal model?
