Ancient Greek philosophers could not measure anything, so this idea was at least somewhat plausible. Modern philosophers have no such excuse. We can simply measure the temperature of the water buckets and accept that our hands are very poor thermometers. Leaving aside the very difficult issue of the measurement problem in quantum mechanics, the last 200 or so years of science have clearly demonstrated that objective reality exists.

>We can simply measure

That "simply" is doing a lot of work there. Measurement is never simple, or correct. Yes, it's much, much more precise than it was in the past, but it's never exact. Until May 2019, the magnitude of many of the units composing the SI system of measurement, including most of those used in the measurement of electricity and light, were highly dependent upon the stability of a 142-year-old, golf-ball-sized cylinder of metal stored in a vault in France. The mass of this cylinder drifts when compared to copies, and nobody knows why. Yeah, the effect is super tiny, but the measurements are demonstrably _not precise_

Of course measurements are always imperfect. The point is that an objective reality exists that can be measured. Which piece of rock we use to compare other masses to does not change that.

I agree that in usual practice, we can assume that there is a measurable, objective reality. However, once you get to the limits of human knowledge, everything starts shifting like quicksand and it becomes less obvious that there's an objective reality that we all share.

How does that in any way prove your point? What if all the measuring devices, their history, this very conversation, what if all of that was a hallucination?

How would you know? How do you propose we definitely prove it isn't?

Ancient greek's could surely measure some things, how else did they build those buildings?

You've declared we can measure everything important so reality is objective, but quantum physics suggests the things we can't measure may be astronomically large. The physicists who subscribe to the many world's theory believe there's a near infinite assortment of humans we cannot percieve or effectively measure, for example, and our own experience of self is inaccurate as we don't percieve ourselves to be branching in time.

I don't think measurements solve the problem of the uncertainty of reality.

Oh really? So you mean things like the no-cloning theorem, no-copying theorem, the whole idea of quantum indeterminacy, and the fact that actual randomness exists gives you evidence for objective reality? Actually, it's exactly the opposite. A =/= A. Even if there was objective reality, it's not available to us.

https://en.m.wikipedia.org/wiki/No-cloning_theorem

https://en.m.wikipedia.org/wiki/Quantum_indeterminacy

https://en.m.wikipedia.org/wiki/Bell%27s_theorem

You've got mounds and mounds of evidence for an objective and constant reality, and a few conundrums to unravel, and you then say "we don't know anything!" That's completely irrational. It sounds to me like you are looking to find data to fit your theory, you are HOPING we are in a simulation, and throwing out the baby with the bathwater.

I find this whole conversation so incredibly funny. Go tell a person serving a life-time jail sentence that what they are experiencing is not an objective reality. Day in and day out, the same cell, the same 24 hour cycle. A gazelle being eaten alive by a group of hyenas. A person jumping off a building to commit suicide. All of these things are simply illusions created by something, who knows what. Even though we don't know anything about THAT part, you are certain of it.

You've seen some goofy particles and have some fun mental puzzles to unlock so yeah, none of it is real!

There's undoubtedly shared aspects of reality and I don't think anyone seriously thinks psychedelics can produce water in a desert. I think the main benefit is psychedelics show you a different mental perspective on objective/shared reality and can shift your ego/identity in a radical way temporarily. Reality is "subjective" in the sense that your beliefs/identity/ego/brain-chemistry make up a huge part of your experience and those aspects can be altered dramatically. Telling someone serving a life sentence that could actually be useful to them. You see a lot of them turn to religion. That being said I eyeroll as well when someone says we're probably living in a simulation, but there is a lot we still don't know lol

The measurement problem is indeed profoundly weird and nobody has a good explanation for it. However, I doubt that you are going to be able to resolve quantum effects when discussing the temperature of two buckets of water.

>How do you know anything is objectively real and not a product of some brain process?

If that's true, then I know that brain processes are real.

Brain doesn't have resources to simulate reality all the way down.

The brain does have the resources to do so, actually. This is variously called dreaming, psychosis, or similar.

Dreaming is a limited simulation, not on the level of reality.

How do you know? We haven't even established what reality is or whether it exists. For all you know, this entire argument could be a figment of your imagination and so could your perception of the rest of reality.

We established the magnitude of the avogadro number, objects so complex have no chance to fully fit in imagination.

So you're saying the fact that your imagination is limited is proof?

I believe in myself more than that, sorry.

[also again, how do you know the Avogadro constant is real?]

Beliefs have no effect on reality, sorry.

Not sure what you mean by real there, the Avogadro number expresses precision at which you need to simulate reality to get something believable and a brain simply isn't big enough for this in purely quantitative terms.

Beliefs are reality.

> a brain simply isn't big enough for this in purely quantitative terms [quotation needed].

And again, what if all of this, avogadro numbers, hacker news, your conception of reality all were a hallucination? How would you know? How can you definitely prove it is not?

Hallucination with such details is not a mere hallucination, but a conspiracy. If the conspiracy is flawless, it's meaningless to differentiate it from reality, it's literally precise equivalence. It's a more complex theory than realism too.