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If you decide to defer "what is true?" to your tribe; you're still making the decision of "is this true or not", just adding in "what does the tribe think?" as another factor. As we cannot communicate perfectly, it's actually "What do I think the tribe thinks?" and even less likely to be a useful input.

We keep doing that, then blaming the tribe for our misconceptions.

I see the language surrounding "tribes" a lot, and I wonder if the people using that language naturally and spontaneously evolved it, or if they encountered it somewhere - perhaps in their own "area", which they definitely wouldn't call their own tribe. The conceptual framework of tribes, in this context, seems to be applied similarly whenever I hear about it. And then similarly, the people who talk about tribalism seem to have decided, that they have risen above such things.
"Tribe" is not the best word in this context; it implies more connection... The group of people one looks to for confirmation of perceptions need not be "people you know and trust", just "people around you."

However, I still hold that the opinion of 10 idiots is not intrinsically better than the opinion of a single idiot.

>they have risen above such things.

We physically don't live in tribes, so it's a fallacy to mentally live in one. Being born in a tribe practically predetermines your life for the worse - takes out opportunity for change and immigration.

i'm going out on a limb to say the comment wasn't about the word "tribe" or the merit of a tribe, it was about how people mimic each other without thinking. if what you think of as reality is determined by the group it will be in the million ways you never would've thought about.

this is why people talk so often in tropes: the thoughts they're expressing aren't their own, they're just repeating tropes they hear. this way of talking of your tribe is just an example trope.

Do most people function like that in your honest opinion? Do you?
What's the operational difference between that and any language acquisition? If your implication is that we're entirely constructed from our influences and that therefore no part of us is original, it's very silly, very linear thinking. We're each unique assemblages of influences, and most of our utterances of any significant length are unique.

edit: neither of our comments have ever been written before.

> I wonder if the people using that language naturally and spontaneously evolved it, or if they encountered it somewhere - perhaps in their own "area", which they definitely wouldn't call their own tribe.

What's the difference you're drawing here? Isn't natural language evolution the same thing as picking things up from the people you hang out with?

(But to answer the question I think you're asking, I think the terminology spread from https://slatestarcodex.com/2014/09/30/i-can-tolerate-anythin... )

I think tribe in this context is "social unit of size and type humans spent most of their evolutionary history in, are best adapted to".
> I wonder if the people using that language naturally and spontaneously evolved it

This doesn't make sense. You can't spontaneously evolve your own language; it's not a language until you've explained it to someone, and to do that, you'll have to use another language (whether verbal or physical.) "Tribe" is a shorthand that points at a few common meanings and a few less common ones, in at least English, and probably a few other languages. If you're confused about the meaning of the speaker, you ask specific questions in order to clarify it. If the speaker starts to get squirrelly about the meaning of the words they're using, suspect that they're repeating something they heard somewhere. When the same words in the same context shift meaning, that's called equivocation.

I, myself, proudly declare alliances to particular "tribes." Talking about tribal thinking doesn't imply that you think you're above it. Implying in sarcastic passive voice that people who talk about "tribes" are actually members of tribes is a self-own that I don't understand the point of.

It's only because we're both members of the English-speaking community that we have any means of communicating over the web.

> Implying in sarcastic passive voice that people who talk about "tribes" are actually members of tribes is a self-own that I don't understand the point of.

Have you actually been on the internet recently? Holy hell. Its rife with people who think they're rising above everyone who isn't a free thinker! And the articles about rising above these petty allegiances are wildly upvoted!!!

You're really demonstrating a lack of awareness about the culture of this website and many others. I can't believe you read the comment I was responding to and thought "hey, this person doesn't think they're rising above 'tribal' thinking".

And yeah, I'm not sure about whether they precisely think they're in that position or not, so I used passive voice. I will become sued by you. Passive voice can be good, actually.

Our values are somewhat driven by consensus, and since we project onto the world the things we already know/believe in, I would say we do live in a reality partially defined by consensus, as far as we perceive it.

I don't think you could demonstrate that you're not living in a reality by consensus. That would be proving a negative anyway.

yeah, this is mostly true...see for example the entire academic school of existential psychology known as Terror Management Theory...there are a number of good books in this area, such as The Worm at the Core: The Role of Death in Life...also see the book Corruption of Reality by Schumaker...

basically these books and the entire TMT field derives from anthropology and sees mankind as a social animal adapted to his environment, and that we are shaped by evolution to be adapted to our environment as a social animal and that nearly everything about mankind is some sort of evolutionary adaption, including our definition of reality...you might say that reality is defined socially...we are social animals, after all...

one of schumaker's arguments is that because of our awareness of inevitable death, we filter and corrupt reality as part of an adaptation to our environment...we do this as cultural entities and not as individuals

You probably meant to write "evolutionary psychology" instead of "existential psychology" ?
no, but you could say that existential psychology as it mainly exists today is merely a subset of evolutionary psychology.
Evolutionary psychology has been critiqued for being too essentialist, and essentialism and existentialism are relatively opposite concepts, so I'm curious as to how the situation you describe has come about.
sounds like word salad to me, but hey, that's just me...
I don't understand why you said what you said then, or how you can understand what you said yourself.
Psychology has a lot of small niches that didn’t make it into popular culture.
Article touches on a lot of 19th century pragmatist discussions on truth. William James gives a succinct description of the relationship between reality and consensus, and abstract/concrete ideas:

"The popular notion is that a true idea must copy its reality. Like other popular views, this one follows the analogy of the most usual experience. Our true ideas of sensible things do indeed copy them. Shut your eyes and think of yonder clock on the wall, and you get just such a true picture or copy of its dial. But your idea of its 'works' (unless you are a clockmaker) is much less of a copy, yet it passes muster, for it in no way clashes with reality. Even though it should shrink to the mere word 'works', that word still serves you truly; and when you speak of the 'time-keeping function' of the clock, or of its spring's 'elasticity', it is hard to see exactly what your ideas can copy"

So it is true that we 'make truth', but we do not make it as we please, as truth-making at some level is a discourse with physical reality and has to cohere.

> [...] it is true that we 'make truth', but we do not make it as we please, as truth-making at some level is a discourse with physical reality and has to cohere.

I love this. Thank you.

> abstract/concrete ideas

If by "idea" you mean "concept", then they can only be abstract. Images are of concrete things.

"and when you speak of the 'time-keeping function' of the clock, or of its spring's 'elasticity', it is hard to see exactly what your ideas can copy"

This sounds very imagist and Humean. Take any principle or any concept. Can you see the law of contradiction? The primality of numbers? That the sum of the angles of all triangles is 180 degrees? What about your concept of triangle? No, not the image in your mind right now. That's just one particular triangle with definite color and shape. I mean the concept of triangularity, that which is true of all triangles and that which makes the aforementioned law of triangles true. You can't imagine that either.

Indeed, this is the basis for the Aristotelian proof of the immateriality of the intellect. If all material things are concrete (this or that triangle), and all concepts are universal (they apply to multiple things but do not exist on their own as such), then the intellect is not material. For if it was material, then it could not "contain" abstract concepts, only concrete images of particular triangles.

This is William James’ pragmatism viewpoint of consciousness, which states that the mind optimizes it’s view of reality based on what it useful and not what is true.
What is useful usually correlates with truth though.

The mind can be though of as a compressed predictor. Compression is important to save energy, there's no need to imagine all the gears of the watch if the goal is just to make a good guess as to when the hand will hit a certain number.

Sure, it’s a 150 year old theory of the mind, understanding it is mostly for historical and background purposes. My comment was mostly to give key search terms for anyone interested in diving deeper.
This makes no sense. This is about filter bubbles, right? With a dose solipsism so that minds can bend reality? Whether you or someone else or everyone else remembers or misremembers or not remembers the color of your first car has no bearing on the color or the existence of your first car. It has nothing to do with consciousness either, a photo of the car can also tell you what color it was. You or a group you belong to can hold all kind of believes about the world, consistent or not with reality. You can change or forget them but those believes will not alter reality. Or maybe I just don't get the point.
But what you believe alters reality, there’s a feedback loop involved.

I get your point that the color of your first car won’t change, but is there even an objective color to that car? My dad is colorblind and sees some colors differently than me. What’s the real one? If the numbers were reversed and the majority of population perceived as colorblind people do while I would be the minority, would that change the color of the car?

I bet you’d say of course not because we can, say, measure the wavelength of the light deflected off the car at noon and agree on a color name based on the result. And I agree with that. But still, the color as perceived by someone can change reality. Just imagine a command such as “follow the red car” and whether the person carrying out the command is colorblind or not.

Of course, there are real-life examples where the collective perception of reality ends up changing the actual reality and that are far more concerning than a car’s color (enough people believing something has led to wars, stonings, etc)

Of course, there are real-life examples where the collective perception of reality ends up changing the actual reality and that are far more concerning than a car’s color (enough people believing something has led to wars, stonings, etc)

I mean that is uncontroversial but one has to be careful. Perceptions and believes about one thing might affect the course of the future and things in the world, it will however not affect the thing you perceived. Your perception and believe about the color of the car can have all kind of effects in the world but they have no effect on the actual color of the car.

Black and blue, or white and gold?
How is that relevant?
https://en.wikipedia.org/wiki/The_dress : a viral tweet which triggered a huge discussion of colour illusion. Colour really is perceptual.

There is, once you get sufficiently pedantic, no such thing as the "actual colour" of the car. You can say things like "spectrally within 1% of Pantone Red 032C under standardised lighting conditions", but the range of responses that will produce in traditional or digital photographs and then on screens and human eyeballs is much wider.

I'm not clear whether tomlockwood is trying to define "real" as "consensus (perception of) reality"?

I'm not really trying to define anything - but yeah, unless we concretely set the pantone of the car by cross-referencing it or something, maybe that colour is still up for debate? The pantone thing would be the microscope equivalent in the post.
No, the color of the car is never up for debate, what is up for debate are your believes about what the color is or how to best describe or quantify what you perceive or belief.
How would you tell?
Tell what?
That the colour of the car wasn't up for debate. What would you measure to determine qualities like this aren't up for debate?
You could measure something like the bidirectional scattering distribution function [1] including its wavelength dependence. Or something even fancier that accounts for polarization and displacement due to subsurface scattering and what not. The important thing is that you can objectively quantify the color and appearance of the car in great detail mostly limited by your dedication and budget. And with that information you could recreate the color of the car and how the paint looks under some given lighting conditions which can also be quantified. There is really nothing to be debated here, at best maybe the fidelity and sophistication of an realization of this method and whether it is good enough for a given purpose.

And I just say this, there is nothing to be measured in order to determine whether something is up for debate or not. This is a question of logic and philosophy and physics. Being up for debate means that there must be different opinions. This can happen due to a lack of information or knowledge. Or due to unspecified assumptions. And probably more. Whether you should have high or low tax rates is up for debate. This right answer will depend on your goals. On the behavior of people and societies and your knowledge of and assumption about those things. About whom do you care, who is affected how? The better you know how things work and the clearer your goals are, the less room will there be for debate.

But what could you debate about the physical properties of the paint of the car? They are facts of the universe - at least unless or our understanding of the universe is really radically wrong. You can measure them. But opinions you can only have about relating things, not what the color is but how it looks to you. What it reminds you of. How you name or describe it. What it looks to a color blind person. What you think it looks to a color blind person. Whether it was worth the money. Whether it should be changed.

[1] https://en.wikipedia.org/wiki/Bidirectional_scattering_distr...

> And I just say this, there is nothing to be measured in order to determine whether something is up for debate or not. This is a question of logic and philosophy and physics. Being up for debate means that there must be different opinions.

But there are different opinions about what colour things are.

> They are facts of the universe

What would you measure to determine that the facts of the universe don't change when you look away?

But there are different opinions about what colour things are.

You might have the opinion that the bowl on the table in front contains 200 M&Ms while I think that there are at least 300. You might change your mind and switch to 150. Nothing of that changes the fact that the bowl contains 217 M&Ms.

What would you measure to determine that the facts of the universe don't change when you look away?

I would just ask someone that looked while I wasn't. More seriously, you just have to stop somewhere. You can not draw any conclusions if you consider the possibility that the universe might become two dimensional any moment and one plus one afterwards no longer equals two. But even if the electromagnetic properties of atoms vary over time or when no one looks, there would still be a possibility - at least a theoretical one - to objectively characterize the color, now you just have to deal with a reflectivity that not only varies with wavelength and angel and so on but also time and number of onlookers.

> You can not draw any conclusions if you consider the possibility that the universe might become two dimensional any moment and one plus one afterwards no longer equals two.

It really might though. There could be a false vacuum. And yet, here I am, drawing conclusions constantly.

But considering vacuum decay is not the same as allowing arbitrary things. And I didn't mean concluding which job offer to take which is hardly affected by the nature of the vacuum. If you, for example, seriously consider that physical laws might change any moment, this should probably influence your decisions. If you see it as some purely theoretical possibility with probability ten to ten to the ten to the... then you can ignore it for all practical purposes, if you think it happens with fifty percent probability in the next hour might be worth considering.
> But considering vacuum decay is not the same as allowing arbitrary things.

That's not what I'm "allowing" though.

Whether or not objective reality exists, I'm still going to make decisions.

But not rational ones.
So what you're saying, then, is that if objective reality doesn't exist, it's not possible to make rational decisions. Please, prove objective reality, exists. If you're not capable of making rational decisions, because the universe isn't objective, any proof you produce is irrational, but you may still claim to have proven objective reality exists, on account of the irrationality.

It seems that we both agree that its not possible for people in non-objective realities to rationally decide objective reality exists!

> The important thing is that you can objectively quantify the color and appearance of the car in great detail mostly limited by your dedication and budget

I used to think that, but my current belief is that there is no objective reality. I don’t mean you’re a figment of my imagination or I’m one of yours (though if we want to go down that philosophical rabbit hole, how could we refute either possibility), but that I now believe reality is not objective, it just is. I no longer believe there is a clear limit between subjects and objects. I think reality is whatever it is, and then our subjective experience is whatever our minds make out of the input from our senses, and anything objective is just whatever enough subjective people agree in consensus. In the vast majority of cases, the simplified vision that there’s an objective reality we can grasp given enough time and resources works well enough to appear true, but it’s important to stay aware of our limitations (I believe, our insurmountable limitations) in completely (to be fair, you did write “in great detail”), reliably, “objectively” arriving at a specific truth about some arbitrary part of reality. (Edited for typos)

This is just somewhat conflating a lot of things. There is a dress with some colors, there is a photo of that dress with different colors because of the specific lighting conditions the photo was taken under and whatever processing the camera performed, and then there are the colors people perceive when looking at the photo, again influenced by all kind of factors. And there is reality to all of them, the actual color of the dress, the pixel values in the photo, and the perceived colors. But whatever color you see looking at the photo does not change the pixel values in the photo, and the pixel values in the photo do not change the spectral properties of the actual dress.
> This makes no sense.

Statement mis-identifying personal state of mind as extrinsic property?

> (rest of comment)

Simple assertions about personal world-model?

> Or maybe I just don't get the point.

Definitely get your feels though. The article doesn't have teeth. However...

Are dreams "reality"? Certainly you experience them. At the very least they are capable of forming vivid memories, no? Heck, if you really want, you can even experiment with lucid dreaming and discover "dream laws". However, dream experiences don't operationalize in the same way as waking life experiences. If you have a really mind-blowing glass of water in a dream, I don't know of a good way to get friends to experience that too.

Should we go full Scientist TM and say that reality is discoverable and reproducible? Perhaps. Elements that operationalize in this way are friggin' useful.

However, that one time the sound of a breeze over a summer lake brought you to tears is not "reproducible" in any meaningful way. That specific memory is closer to a dream in many ways, since it mostly operates as memory. So was that experience "not real"?

Okay, so maybe "reality" isn't just Scientific Laws or whatever? Maybe the article has a point?

Personally, I find the act of asking these questions and seriously engaging with them to be fruitful. They can highlight the boundaries, edge cases, and bugs in a mental model. Humans can get into all sorts of interesting mind-states. In my experience, the "makes no sense" feeling is usually an indicator that I've failed to engage my mirror neurons and simulate said mind-state.

I'm not sure about what I've read, but I have a headache now.
I think the consensus is that you do not have a headache. Obviously you are only imagining it.
This is not the same concept but it reminded me of the Collective Cognitive Imperative as introduced by Julian Jaynes: https://en.wikipedia.org/wiki/Collective_cognitive_imperativ...

I may be misremembering (which, in a way, I suppose would be fit for the topic) but I don’t recall the emphasis on “joining a cult” that I get from the Wikipedia entry. My recollection is more along the lines of what enough people believe and understand influences what is perceived as real (a god speaking through an oracle) and what isn’t.

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This is one of the fundamental mysteries of quantum mechanics called the "observer effect". Experiments have proven that particles change their essence at the instant moment they are being observed. This discussion is not only philosophical, we can prove perception changes everything.

https://m.youtube.com/watch?v=ZH9OfoM1MiU

That popsci video is — out of necessity, this is not a criticism of those in it — a massive oversimplification.

One of the arguments on this topic is if there even is an observer effect at all, with one alternative being that the quantum wave function never collapses, instead it is our own wave function becoming entangled with that of the particles we observe: the part of us which observes |A> is correlated with the part of the particle wave function in state |A>, the part of us which observes |B> with the part of the particle wave function in state |B>.

(And I'm also oversimplifying, because I’m still learning this stuff).

The one issue I have always had with the 'observer' problem is that everything is 'seen' by something. But then I am a dullard on this junk and probably have it wildly wrong :)
My (limited) understanding is that the problem you’re raising is exactly why quantum computers are difficult.

I think it’s something like: yes, everything is “seen” by the rest of the universe, but “seeing” is done with discreet did-or-didnt happen events (mostly photons) which can be suppressed.

The observer effect has nothing to do with observers, it's just that entangling with large systems decoheres small systems where you can observe quantum effects.
We certainly cannot prove that perception changes everything. The greatest mistake physicists continue to make is using common words that mean particular things to refer to something utterly different. “Observer” is as fine an example as any. The resulting misinterpretations, even by physicists themselves, were completely avoidable without launching the quantum fluffery industry, but here we are and remain.
right, "observer" essentially means "interact with in any way that exchanges information, in the quantum sense of the word information"

Still though, the fact that some states remain indeterminate until that interaction takes place means the universe holds its cards pretty close.

I expected that the article will draw an analogy with quantum mechanics (with "refresh" corresponding to measurement and entanglement, "forgetting" resembling a quantum eraser), or maybe lazy evaluation, but it went into search bubbling instead. Still a fun analogy, and nicely written, but not quite sure what's the point of the article.
This set of ideas is exceedingly interesting for use in fiction. There’s been quite a few different examples in the past, and I’m working on another one right now.

I absolutely appreciated the extra perspective.

Bit heavy on the metaphor here? This reminds me a lot of Three Body Problem, one of the premises of which is that there is an alien civilisation that can mess with particle accelerators to prevent us from discovering how the universe actually works.
Even unfavourably comparing something I wrote to that book is a huge compliment!
It seems to me that the essay is attempting to describe the Google search engine.
I'm a logical person. Thought myself well-grounded, agnostic after leaving Mormonism...etc... then last year I went down a rabbit hole on some Mandela effects, esp. ones that flip/flop.

Short of it is - the Movie Apollo 13...

I remembered it has "Houston we have a problem!" with frantic Tom Hanks. I was reading how it's the most misquoted movie line, and is actually "Houston we've had", and that a lot of people have seen this flip back and forth between the two states.

Well, I double checked on youtube and sure enough... Houston We've HAD a problem was the correct/current iteration. Tom Hanks was also a bit more 'cool' like I'd imagine the real astronauts were...

My wife watched it with me and can verify.

Fast forward just 3 days. I'm reading a list of Mandela Effects still intrigued by things like the Cornucopia in Fruit of the Loom never existing...

On this list: Apollo 13 Movie, previous: Houston We've Had a problem, current: Houston we HAVE a problem.

Well, I immediately thought it was a typo. Till I opened youtube. It's now a more frantic Tom Hanks + Houston we HAVE a problem and different camera angles, etc.

Oddly, just about all the links out there claiming it's the most 'misquoted movieline' are still there on many different sites from Buzzfeed to Ebaumsworld. Yet, that ONLY works if the ACTUAL line is Houston We've Had a Problem, because as you can probably attest -- in all of pop culture when that line is uttered it is almost 100% "Houston We have a Problem".

In fact when I first saw the We've Had version, I chalked it up to bad memory because ...well it's just such an ubiquitous line and is used everywhere, in countless movies/tv-shows etc...

My wife can attest - she witnessed the flip too.

For like 3 months after that, I kinda went down some weird rabbit holes trying to find some control of the 'matrix' or simulation...before coming back down to earth. It rocked my world view.

Personally, I think we're either a simulation or that the entire universe is conscious and what we think we're experiencing is a dream of sorts or something, the only way I'd buy multiverse is maybe if the multiverse is reaching some sort of entropy so worlds are 'popping' like bubbles and colliding so that people from different timelines end up together and dispute reality.

If it's a simulation though, I was thinking this same thought that - everything we perceive or believe is a result of consensus, but I don't even think it's total human consensus -as much as it is potential network consensus... if 51% of the people you're likely to connect/network with online or off believe that it's Houston We've Had a Problem, that's what you'll see... say there's a deadly pandemic and people are dropping like flies, maybe those networks change faster... and thus things flip flop back and forth more...

The biggest Mandela Effects seem to be related to popular content, so it's usually things where there easily has the majority of people who at least have a memory of something one way or another. For instance there's lots of biblical MEs like there used to be a scripture about the lion laying down w/ the lamb, but it never happened. There's also many spots in the bible where it feels like the word 'things' should be 'possessions' and 'alien' should be 'stranger'... and I don't even believe in the bible, some would say it's 'Satan', but what's he have against Apollo 13 or the Fruit of the Loom Cornucopia? or "Objects in Mirror MAY Appear closer than they appear" (may be is actually 'Can').

I think it could also be related to quantum physics double eraser / delayed choice experiments, but I'm not convinced that quantum physics doesn't actually lead us to discovering we're simulations. To b...

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Probably, the first website you saw said something along the lines of "the movie misquoted the radio communications".
If my something changes, and someone "remembers" it always being like that, that sounds like gaslighting.
Gaslighting works. The foundation of western culture is the greeks right? Because the greeks didnt get their knowledge from Kemet (egypt) before burning the library of alexandria right? I mean yeah the library got burnt but im sure there wasnt much in there right?

And the maya... they had their thousands of books reduced to three. But we know about their culture because of cortez's descriptions right? They were awful bloodthirsty savages right? The three books left from their culture must have perfectly summed it up right?

Reality is built on gaslighting at a point

It's an interesting idea which I'm not ready to outright dismiss, but I think we have some evidence that it cannot be completely true. There are universal laws of physics that have given shape to this reality which are not a result of conscious effort to conjure into existence. Look to things like germ theory causing illness well before anyone was consciously aware that it was a thing. Doctors were outright offended at the idea that they could in part be causing patient illness through unsanitary conditions.

Still, I've been reading stories like some of those mentioned in this thread (ie: mandala effects) for years which really does make me wonder.

I think my view of it tends to be that it's not that we're consciously creating or altering reality merely by having specific thoughts or through some type of force of will, but rather that the things we focus on tend to be shaped by that focus, because the focus and attention manifests in physical actions taken by us where we explore, discover, and build things related to that particular rabbit hole.

It's how I've started thinking about the personal projects I work on. The quality of what I produce is a function of the quality of the initial idea + how much focus and attention I give to it.

So on an individual level, if I continually have thoughts about a certain subject, these thoughts are likely to manifest in me taking actions which materially changes the universe. For example, I might be overweight and have thoughts about losing the weight, which might eventually lead to diet and exercise.

On a more macro scale, I think if people are continually exposed to something they acclimate towards it. It becomes more acceptable. They might start to change their world views. So what enters into the consensus of collective consciousness (ie: large groups of people agreeing on, or at least focusing on a particular subject), it's people being continually pushed narratives and propaganda, as well as everyone being subject to the same laws of physics. For example, Trump either is or isn't a liar depending on the media sources you typically listen to. Another example would be climate change entering the masses consciousness and now (slowly) action being taken to combat it.

This collective belief, similar to the losing weight example on an individual level, leads to collective action on a macro level. The universe bends to our will, but only if we are conscious enough to manifest that will. Until then we're just automatica burning the planet.

"Imagine if you forgot what one of the rooms in your house looked like, and when you returned, it had changed, it was “refreshed”. It had refreshed, not into some absurd wonderland of glowing fungi and strange creatures, but to one consistent with what you believed a room ought to be. Perhaps there was a lightswitch outside, that now instead of turning on the fluorescent globe, turned on a LED one. Maybe the books on the shelves had refreshed, but the ones you remembered and remembered reading, had remained."

It's a bit of a spoiler to link it in this context, it's really better to stumble on to this cold, but you don't have to imagine: https://www.youtube.com/watch?v=ubNF9QNEQLA

Well if the world were to operate that way, and the consensus was tthat it does not operate that way, it would no longer operate that way, presumably ever again.
I am reminded of the Phillip K Dick essay/speech "How to Build a Universe That Doesn’t Fall Apart Two Days Later". https://urbigenous.net/library/how_to_build.html

My particular favourite quote is:

One day a girl college student in Canada asked me to define reality for her, for a paper she was writing for her philosophy class. She wanted a one-sentence answer. I thought about it and finally said, “Reality is that which, when you stop believing in it, doesn’t go away.” That’s all I could come up with.

Huge compliment, pkd is my favourite author. Thank you!
While I don't think that consensus can bend the laws of physics, I believe that humans largely construct their social reality.

Buddhists often refer to things which are 'conditioned', i.e. dependent on conditions for their continued existence. Many so called truths humans believe in are conditioned, and also require maintenance (continued belief, and communication of the idea, embedding into institutions and laws etc...) to keep the alive.

See: https://www.amazon.com/Social-Construction-Reality-Sociology...

As far as I have been able to tell, we do live in such a world: reality is a dream, and the only truly concrete fact is subjective awareness.

OP asks, "How would someone know they lived in such a world?"

Well if you study and practice, like, at all, you find that "magical thinking" of what some call "co-creation" happens. If you keep going like that, you find that reality is fluid, up to the point where you can materialize or de-materialize physical objects including your own body. The time delay between imagining something and having it exist in the "real" world reduces. (This is the resolution of the riddle "Make the inside like the outside and the outside like the inside.") At that point, if you have your head on straight, you start to wonder who is really doing all this? Is it "I"? From there you begin to realize that your own "I" is an illusion and there is only one "I", the I of the Universe.

So that's the way "out".

"Imagine if forgotten reality was up for debate! Was your first car yellow, or yellow-green? Did chicken always taste like that?"

Imagined reality's memory is up for debate internally since your memories change over time, it is almost like the choice of debate is being taken away between the first version of a memory and subsequent versions as time passes while we keep retelling our memories to ourselves.

"Now imagine there was an algorithm that received signals about your beliefs, and refreshed your environment into something that aligned with them. The algorithm would decide, if you felt that there was a truth about the universe, to show you things consistent with that, and nothing inconsistent with it."

you just described recommendation engines lol

Pretty sure that was exactly the point of that segment.