when I say that an unperceived object neither exists nor does not exist, I am not saying that objects go in and out of reality. I am saying that outside all possible cognition, conception, designation, or disclosure, there is nothing of which existence or non-existence can be meaningfully asserted. You cannot truthfully say “it exists,” because existence is never encountered except in disclosure. But you also cannot say “it does not exist,” because there is no determinate object there to which the predicate “non-existent” could attach. — Wayfarer

When I perceive a brick in front of me, I have developed beliefs about an object: the brick. This includes the belief, "there is [=exists] a brick at some approximate distance from me". If I close my eyes, I no longer perceive the brick, but my beliefs persist: I continue to belief this brick is there [=exists] at that location. Continued perception is not necessary to maintain the belief. The belief is true because it corresponds to an aspect of reality. You omit belief formation and persistence from your account. This is called object permanence: "Knowing* that objects continue to exist when they cannot be directly observed or sensed." It's a capacity we develop as infants. (See: this) Undoubtedly, you went through this stage of development, and yet you're now expressing doubt about this.

*"Knowing" is true, justified belief. So I CAN truthfully say "the brick exists even though I do not currently see it". Do you deny the belief is justified?

Accordingly, existence and non-existence are not free-floating properties of a reality wholly outside cognition; they are predicates that arise only within the context of intelligibility. Outside that context, nothing positive or negative can be said at all. It's not a dramatic claim. — Wayfarer

Denying object permanence, which you learned in your first year of life, is a dramatic claim.

Existence isn't a property at all. To exist means to be part of the world. To say, "X exists" means that the word "X" has a real-world referrent. We apply the term, "non-existence" to concepts (mental objects) with no referrent in the world.

If you take any object — this rock, that tree — and ask, “Does it exist when unperceived?” you have already brought it into cognition. To refer to it, designate it, or even imagine its absence is already to posit it as an object for thought. The very act of asking the question places the object within the space of meaning and predication. — Wayfarer

You use "object" in 3 incompatible ways:
1) to refer to a tangible, real-world object
2) to refer to the direct sense impression you experience as you look at it (directly perceiving it as a gestalt).
3) to refer to the mental object in your memory that you use in your reasoning as a proxy (referrent) for the tangible real world object that you are not presently looking at (also a gestalt).

You then conflate 2 or more of these senses of the word and arrive at absurdities. I think if you treated these as distinctions, and acknowledged that we establish beliefs about real-world objects, many of your issues would disappear. Consider,"If you take any object — this rock, that tree — and ask, “Does it exist when unperceived?” The real world object (rock, tree...) exists irrespective of our ever having perceived it. The perception of the object exists only while perceiving it, and the mental concept/picture of the object exists as a memory of the perception along with beliefs about the object.

The gestalt of tree (directly perceived or the memory object) reflects the way we cognitively organize our perceptions/conceptions - but it nevertheless corresponds to a functional object in the real world, an object about which true statements can be made - including it's interactions with other functional (and real) elements of reality.

‘Does the moon continue to exist when nobody is looking at it?’ " — Wayfarer

I believe the real-world object that we refer to as "the moon" exists when no one is looking at it; this is entailed by my belief in object permanance and my beliefs about this particular object. I believe real world objects have no ontological dependency on being either perceived directly, or remembered.

Is there someting wrong with this answer? Is my stated belief (in bold) unjustified?

Why did Einstein ask this? My understanding is that he was challenging the notion that observation plays a role in determining physical realty, an idea suggested by the Copenhagan interpretation of QM. His implied answer was, "of course not!".

Nothing you've described is inconsistent with physicalism.

That’s not surprising because I’m in agreement with most of what physicalism says. I was narrowing down what part of existence we know. Existence as a whole and the mechanism of existence is not part of that. So to say;

-that mind is foundational to existence;

Is to conflate that bit which isn’t part of it with the existence we know. The bit of existence which we experience isn’t all of existence and isn’t foundational. This is self evident because we have limited capacities to experience and know things.

This is a mereological issue. Just because objects are reducible to particles doesn't imply they are not actual, functional entities in the world. By "functional", I mean that they can be analyzed in terms of their interactions with other functional entities.

Yes, but I’m saying something broader than that. For example in a thought experiment I can say the Earth is a being, Gaia for Gaia the physical world might be like a thin protective layer in her skin, that she is barely aware of and her family is made up of other planets and stars. In conversation what to her is the equivalent of a word spoken in a minute might in our terms be a few million years of seismic events and most of her life is an experience of transcendent realities entirely inconceivable to us. Rather like comparing our lives to that of an individual cell in our bodies. The cell could not comprehend, or understand anything about our lives and yet we share consciousness and there is a germ of being that the cell feels, which we and Gaia also feel in some way.

‘Does the moon continue t exist when nobody is looking at it?’ Einstein asked Abraham Pais.

Why do you think he asked that question? — Wayfarer

The question is unwarranted (like 'Cartesian doubt'), so why it was asked is philosophically trivial. In a scientific sense, however, Einstein's question exposes the absurdity (i.e. category error) of speculatively extrapolating – as (scientistic quantum-woo) idealists/antirealists tend to do – properties from unmeasured quantum states to interacting (i.e. measured) ergo decoherent states such as "the moon" – after all, strawberries do not get their flavor from 'strawberry-flavored subatomic particles'. :smirk:

The real world object (rock, tree...) exists irrespective of our ever having perceived it — Relativist

This is the whole point at issue. I've given my reasons in detail, if you can't see them, so be it, (although it might be noted that AI has no trouble understanding them). But I see no point in responding further, I'll leave it at that.