Quantum-Intentional Interpretation

In my post on quantum mechanics and consciousness I mentioned a category of quantum interpretations that I call "quantum-intentional interpretations". I defined these as any interpretation that holds that consciousness can be a cause of physical quantum effects.

I want to revise this definition slightly, however. I was conflating two types of ideas. Exactly what aspect of consciousness is acting as a cause? There are two obvious ways of thinking of it:

1. Passive: conscious perception causes physical change.
2. Active: conscious decision of the way in which a quantum system is measured brings about a physical change.

(There may be more ways of thinking about this, but this seems exhaustive me.)

Obviously, the second is more appropriately called the quantum-intentional interpretation since it deals with the intentions of the quantum physicist. I want to use this as the new definition of the term. Interpretations that fall into first of the above distinction should be called quantum-observational interpretations.

There are a couple of reasons I accidentally conflated these two categories. The first is that my understanding of perception is that it needn't be understood as passive. That is to say, any passive description of perception could be phrased so as to be an active description. This is not an immediately obvious point, however. In addition, it's not clear whether or not this is actually true, much less whether or not I am justified in assuming it. Arguing this point would not be important for the discussion, so it is best to avoid implicitly assuming it.

There is a very good reason to make this distinction: one of these two interpretations is very easily refuted. It is easy to show that the quantum-intentional interpretation is plainly ridiculous.

The second is that the quantum-intentional interpretation was just so plainly false. But first, let's see what the most compelling argument in favor of it looks like.

Arguing in Favor of the Quantum-Intentional Interpretation

The technical term for the way a quantum state is measured is called the basis. When one measures a quantum state, one must measure it with respect to basis.

A loose analogy would be to think of the coordinate grid you overlay on top of some two dimensional plane you want to measure. If you want to mathematically describe a coordinate direction, it must be described in terms of a coordinate system. This coordinate system can be changed at will, and there is established mathematics to describe the way in which the math will change as a result. 

Similar to how a coordinate overlay defines what coordinate directions one can use to describe a direction, basis defines the types of measurements we can make on a system. Changing the basis one measures in will change the way a quantum state will be measured and what the outcome will be.

In fact, for every quantum superposition, there is a basis in which to measure it such that it does not behave like a superposition and there will be no probabilistic outcome.

So the question is: if we are able to affect the superposition simply by the way in which we choose to measure it, does that intentional decision change reality? It would seem to be compelling to say yes. After all, a scientist could choose to measure something in one basis rather another, and this decision has made a real change in the stuff itself.

The Quantum-Intentional Interpretation is False

So why is this so ridiculous? That's because it's a category error (you know, that same distinction that has made dualism so passé in contemporary philosophy). There are different kinds of causes, and intentions are the wrong kind of cause to truly act as the kind of explanations we want them to be.

First, a joke. One is touring a physics lab when you see an elaborate device with pieces all around the room. You are intrigued, so you ask what it does. The physicist giving your tour begins to explain each part of the device. Each step it goes through is more elaborate than the next, and it all seems to rely on mechanisms that are being studied elsewhere in the lab, but you can't figure out which part is specifically being studied. At the end of the physicists explanation, you vaguely understand the way every part functions and how they all interact with each other, but you still cannot figure out what is being studied with this device. You ask "what do you study with this device?" In reply, the physicist just laughs and says: "we don't study anything with this device, it's just an elaborate Rube Goldberg device for making coffee."

The physicist has, in a sense, answered your question. He explained what device did in terms of all of the physical workings that are involved in its functioning. The explanation that satisfied you, however, was an explanation about the intentions of those who built the device: the device is for making coffee. The joke, obviously, is that the physicist offered the physical explanation instead of the one that was most helpful. Anyone who has dealt with physicists, or similar creatures, can tell you that this not an unrealistic situation.

When we give an explanation, we can give different kinds of causal explanations. Sometimes a certain kind of causal explanation is, strictly speaking, not an adequate explanation for a question, even if it is not a, strictly speaking, incorrect causal explanation.

When scientist designs a device to measure some quantum state, of course the intentions of the scientist play a factor in how the device ends up behaving. But when a scientist is trying to understand some physical system, they are looking for a physical cause. If someone were to ask why a quantum state is showing the behavior that it is upon measurement, saying that a scientist intentionally designed the apparatus to measure in a certain basis, this would not be an adequate explanation, regardless of whether or not it is a true explanation in some sense. The physicist is looking for a physical cause, and intentions are not a physical cause.

So yes, the intentional choice of measurement basis does, in a sense, cause reality to change. However, that cause is not a physical cause, and would be an inadequate kind of explanation for a physicist studying it.