A couple of days ago, we were looking at the way theoretical physicist Sabine Hossenfelder grapples with the way quantum mechanics has undermined materialism. Whether and how we choose to measure something has a big impact, which makes consciousness very difficult to just explain away.
Here is her most helpful video on the topic (all the more helpful, one might say, because she is so clearly unhappy with the outcome!):
“Does Consciousness Influence Quantum Effects?” (November 19, 2022)
Nobelist Eugene Wigner (1902–1995) was one of the physicists who explored the problem. Hossenfelder points to his famous “Wigner’s friend experiment.” (3:01). Here is an illustration from a different source:
Essentially, as Wigner pointed out in 1961, a basic building block of our universe like the photon can exist in two states at the same time (superposition). So two observers can be correctly seeing two different states. The photon collapses into one state when it is measured.
Hossenfelder argues, “Most physicists think today that a measurement is an interaction with some apparatus. It has nothing to do with whether you or someone else looks at the result, or whether you tell someone about it. But in the early days of quantum mechanics, it was unclear what the mathematics means.” (3:53)
Wait. To say that “a measurement is an interaction with some apparatus” evades the issue. Only a conscious human being can even envision science measurements. The whole cause of the interaction is a conscious human mind with questions about the universe.
If two different people can honestly come to two different conclusions from the same simple experiment, their minds are real and are part of a picture of a much more complex universe than what we might have assumed.
Hossenfelder goes on to say, “No one knows what consciousness is anyway and if you want to calculate the outcome of a measurement in quantum mechanics you don’t need to know. So introducing some psychophysical factors to induce the collapse of the wave-function is just unnecessary word salad.” (7:00)
Again, wait. She admits that “no one knows what consciousness is.” But it is clearly not physical, much as some might wish it to be.
Things do not get any better at 7:05:
Philosophers dislike this interpretation for a different reason, namely because it’s internally inconsistent. You start with assuming that consciousness is not subject to the same laws of nature as everything else because it’s “extra-physical”. But then consciousness interacts with the physical world and that means it’s itself physical because you can test its effects on our observations. It’s the same problem as dualism. If the mind is non-physical, then it doesn’t help you explain observations in the physical world – you can’t have your cake and eat it too.
This sounds confusing because consciousness can, of course, interact with the physical world without being physical for the same reasons as information can interact with the physical world without being material.
Along those lines, what are we to make of “If the mind is non-physical, then it doesn’t help you explain observations in the physical world”?
The human mind, which is clearly non-material, is the only tool we have to explain observations in the physical world. Our minds may or may not be telling us all we want to know. Or not at present. But there is no alternative. There is no other type of mind we can just pull down and use.
If this is a good performance, materialism is in deep trouble.
You may also wish to read Part 1: Quantum physics axed materialism. Many hope the world won’t know. Theoretical physicist Sabine Hossenfelder struggles to explain how quantum mechanics is consistent with materialism. What Hossenfelder appears to mean is that an entirely materialist explanation should work and that physicists are at fault for not explaining.