You're not the only one it puzzles. Esteemed mathematical physicist Sir Roger Penrose adamantly declares that quantum physics must be wrong, deficient or incomplete for exactly that reason. He says that the Universe must be a certain way, and it's the job of science to discern the way it is, independently of any act on our part. But others, for example QBists, say that each act of measurement is unique to a particular observation and therefore that it is inherenently subjective in some sense.

By the way, I don't know if it was C G Jung who said that. Bishop Berkeley, who is often discussed on this forum, certainly said esse est percipe (to be is to be perceived) but he was a long time before Jung. But you're right in saying that quantum physics has opened these cans of worms again, of that there is no question,

I just discussed the same topic in another thread. I think you'll find it interesting, so I'll just copy my answer

My fascination with the processual approach to ontology is a kind of response to speculative ontology (object-oriented ontology and so on). I believe that the "subject" today needs philosophical defense more than ever before. If you're familiar with the works of us contemporaries, I think you'll understand what I'm talking about.
Harman, for instance, argues that the "hammerness" of a hammer is always withdrawn. "Hammerness" is the real being of the hammer as a unified object, which can't be reduced to its relationships with other things (e.g., a hand, a nail, or our thinking). We can't know it completely because:
Objects have "real qualities" that aren't exhausted by their "sensual" manifestations.
Any kind of knowledge is a relation that only reveals aspects of the object, but not its holistic essence.
This withdrawal occurs in three dimensions: the object transcends any attempts to grasp it; it retreats into the background during use; and as a tool, it's always on the verge of breaking, yet remains partially inaccessible.
Harman emphasizes that this isn't skepticism (objects are real) but rather realism: objects exist independently, but their depth is infinite and inaccessible. This distinguishes OOO from relational ontologies, where everything is reduced to connections.


What I Propose:
The modality (or the name can be changed to your liking) of a hammer is its "shadowy depth" (like Harman's), objective and inaccessible in isolation. But when the hammer is used, "hammerness" as a property emerges as an event—dynamic and contextual. This explains why we can't know hammerness statically: it doesn't exist "in the hammer" as a substance, but is born at the boundary of interaction, much like how for Harman, an object is only partially revealed in relationships.

For Harman, the hammer is revealed in its use—we see only one aspect. I propose to refine this: "hammerness" as a property is revealed in an act of participation, an act of encounter, and depends on the participants in the interaction (the hand, the nail, the task, the lighting). For another participant (e.g., a child playing with the hammer) or context (the hammer as a weapon), a different property is revealed, but the hammer's modality remains the same. This helps explain why complete knowledge is impossible: properties infinitely vary in processes, but they never exhaust the modality.

For Harman, the subject is a passive object, equal to others and withdrawn from access. The subject is unremarkable and unnecessary (why do we need it if everything is an object, and the method is objective). In my opinion, on the contrary, the subject (the observer or the "I") is a fully existent being with its own modalities (objective structures, such as the visual system or consciousness). It doesn't disappear or become fully flattened: the subject actively participates in the act of Participation, where properties are revealed. For example, in the case of a red apple, the subject (observer) is one of the participants in the interaction (along with the apple and light), and their modalities (cognitive structures) determine how the event of the property emerges. This overcomes Harman's radicalism, returning a role to the subject in reality, but without idealism: the subject doesn't create properties; it co-participates in their actualization

Some folk would have you believe that consciousness is what collapses the wave function. It isn't. The function is collapsed when measured.

But what, exactly, is a measurement?
https://www.scientificamerican.com/article/quantum-theorys-measurement-problem-may-be-a-poison-pill-for-objective-reality/

Examples of measurements without consciousness:

• A photon hitting a photographic plate and causing a chemical reaction
• Cosmic rays interacting with particles in space
• Radioactive decay triggering a Geiger counter in an empty room
• DNA mutations caused by radiation

Each collapses the wave function. None involve consciousness.

See https://www.nature.com/articles/d41586-025-02342-y

:100:

Suppose each thing is always a 'superposition of possibilities' but that measuring a thing tracks, or records, only one possibility at a time when the measurement apparatus – also a thing – is classical (i.e. local, decoherent). :chin:

But can only be validated by observation a posteriori.

, - to be sure, the account is not settled. There is room for discussion and compromise, and the answer may only be decided by experimentation.

However there are those here who, for their own reasons, will pretend that the issue is settled, and in favour of consciousness being needed to collapse the wave form.

In the Nature survey cited above, only 9% of physicists will agree with them.

Now will come a series of arguments aimed at discounting the view of collapse as measurement, beginning with

↪Banno But are can only be validated by observation a posteriori. — Wayfarer

Note that this is a seperate point - the simple truism that we can only know how things are by looking at how things are. It ignores the difference between somethings being true and being known to be true. A common bit of antirealist rhetoric.

Nevertheless the observer problem can’t be wished away by realist rhetoric.

Sure. Nor is it answered by Indian mysticism.

But maybe quantum mechanics really is magic. Not metaphorical magic, but actual sorcery. We build lasers, computers, and superconductors out of it, but the act of “observation” still works by means unknown — changing the outcome simply by measuring. Engineers can harness it, like magicians who know the words of power, but nobody can finally say why the spell works. It produces miracles daily, on a basis that remains mysterious. If that isn’t sorcery, what is?

Calling it magic is not explaining it. But calling it magic might lead one not to look for a better answer.

Why make the leap to calling it magic? Why not just say: "I don't know, but I will try to find out..."

:up:

Engineers can harness it, like magicians who know the words of power, but nobody can finally say why the spell works. — Wayfarer

:roll:

'I think i can safely say that nobody understands quantum physics' ~ Richard Feynman (who ought to have some credibility, as he won the Nobel Priize in the subject.)

Have another one. :up:

C.G. Jung once said that the world only exists when you consciously perceive it. In that theory, only what I see truly exists. What I do not see, or what I am not aware of, therefore does not exist. — Jan

Welcome to the forum. Given my obsession with metaphysics, I will point out that Jung’s formulation is metaphysics and not science. On the other hand, it is my understanding that Schrodinger‘s cat was a thought experiment intended to show the absurdity of some interpretations of quantum mechanics, not as a serious explanation for an actual phenomenon.

In other words, you are comparing apples and oranges, or to use a word I recently learned, the explanations you described are incommensurable.

'I think i can safely say that nobody understands quantum physics' ~ Richard Feynman — Wayfarer

You interpret that as Feynman saying that engineering is like casting magic spells?

I’m saying there’s a sense in which quantum physics seems like magic. Have a read of Spooky Action in Action

:up:

:up: :up:

You [@Wayfarer] interpret that as Feynman saying that engineering is like casting magic spells? — wonderer1

:smirk:

Yes, with the very large difference being that they work :100:

nobody understands quantum physics' — Wayfarer

If you stopped there, we would have little disagreement.

But in a few posts you will be leaping beyond the obvious truth that we only know stuff with our mind, to the mind created world; to mind not just being an outcome of the way things are, but the reason that things are this way.

Now you may be right; but the evidence available does not support your certainty. And there are conceptual difficulties you have yet to overcome.

It's you who goes past Feynman's aphorism.

But then, this is a philosophy forum, not physicsforum, where this discussion wouldn’t even be tolerated.

...this is a philosophy forum... — Wayfarer

That doesn't validate a leap into proclaiming what is mere speculation.

I’m not ‘proclaiming’ anything. I’m saying that quantum physics is like magic: it produces astonishing results but nobody can really say how. Hence the most embarrassing graph in modern physics. No wonder the staunch realists say it there must be something wrong with it.

I’m not ‘proclaiming’ anything. — Wayfarer

Sure.

The graph isn't embarrassing, as indeed is pointed out repeatedly in the comments. The results from this small survey are not too far form the results in the bigger Nature survey I cited above. (thirty odd compared to 1,100). The Copenhagen interpretation hold steady in both.

To be fair, neither survey included your option, "It's magic".

C.G. Jung once said that the world only exists when you consciously perceive it. — Jan

Back to this. Was he right?

Did the world cease to exist last night while you slept?

What would happen if you were to pretend that it had? If you insisted that events that others claim occurred while you slept did not occur, becasue nothing existed while you were asleep?

How would others treat you?

Would any advantage accrue to you from this exercise? Any at all?

Back to this. Was he right? — Banno

It depends on how you interpret what he was saying alongside what it appears he actually meant.

It depends on how you interpret what he was saying alongside what it appears he actually meant. — I like sushi

Obviously.

So, did the clock on your wall keep moving while you slept, or was there a leap from when you closed your eyes to when you opened them again, no time passing - nothing exists, just things leaping ahead as if time had passed?

Indeed, there would be no period of unconsciousness, since time is a part of the world that supposedly ceases to exist "while you are unconscious"...

There could never be a period in which you are not conscious.

To be fair, neither survey included your option, "It's magic". — Banno

‘Any sufficiently advanced technology is indistinguishable from magic’ ~ Arthur C Clarke. If you don’t think modern information technology is magic, you have a very limited imagination.