9 Illusions That Explain How Your Brain Constructs Reality

[@besmart]

Which illusion hurt your brain the most? Leave a comment and let's see which one wins!

[@saatvikjha4035]

Okay

[@jonahjerryson4913]

Obviously the window spinning one Like "What in the cerebral cortex is GOING ON HERE??"

[@marakiiii]

Yesss

[@karamimamali6139]

I guess everyone gonna say window one

[@TiberiusMoon]

Not in the video but Time. The rate of which we observe energy move matter through space in some shape or form. The faster rate we observe reality the slower time progresses and obviously the slower we observe reality the faster time progresses. This illusion can make a day progress faster or slower and our other senses help influence this like fast or slow music. Even if we were to travel around the speed of light, time may appear to stop but in reality we are still travelling at the speed of light. This illusion is so good its even fooled scientists to think its a universal constant when in reality its an observer constant, because you cant have time without energy moving matter through space in some shape or form. (Even our senses are based on energy moving matter through space in some shape or form and without it we can't observe time!)

[@B00s3]

I got hung up on one thing Joe said... That Ames abandoned art to create these illusions. I'd argue that these illusions are art, he never abandoned it, he just created very unique illusions with his artistic talents.

[@user-ew5vj1sl1u]

Last time someone abandoned art, Poland was split in half.

[@tea.lillith]

Was gonna comment the exact same thing

[@theeverythingchannel9786]

i agree

[@1112viggo]

Sure why not. Anything and everything you can place on a pedestal or put a frame around can be called art. There is no real definition.

[@reddcube]

I wonder if Ai vision is also susceptible to same optical illusions. Because camera are only mimicking human vision I bet only some will work, but then again maybe there are illusions that only work on Ai and not Humans.

[@NetAndyCz]

It is, and there have been several car accidents of autonomous vehicles caused by AI suffering from those optical illusion. Also, the AI is really stupid still (do not let anyone try to tell you it is smart). It is trained to see certain shapes, but it uses really weird probabilistic method to get there and it can be fooled quite easily into "hallucinating" you can have "almost" random noise images that AI (specific AI, mind you) will see letters, numbers, and even images). And there is almost invisible makeup that fools a lot of intelligent cameras that will not detect your face properly. (Optical) illusions for AI are quite a fun topic.

[@stefanperko]

Adversarial examples

[@baddweather6362]

"Reason" by Isaac Asimov follows this exact train of thought and shows the possibility of how an AI could misinterpret their surroundings leading to extremely strange behavior

[@GapWim]

For optical illusions involving depth perception, I guess it would depend if it only has a camera equipped or if it has additional aids such as lidar for example. In the former: yes, the latter:no.

[@danzoom]

Isn't this just like when a phone camera misidentifies a face?

[@amandab.6078]

the constellation one really got me, like if people were on another planet they'd see completely different constellations?? that's so cool. imagine like a scifi story where they're on another planet and they have a totally different set of myths based on a totally different set of constellations

[@emreyurtseven23]

That's why it's all bogus and I have a hard time understanding why so many people believe in it (horoscopes and stuff) in this day and age.

Other cultures HAVE different set of myths!

[@ZennExile]

@@emreyurtseven23 that's just your ego trying to convince you of your superiority. The truth is, only a handful of people at any given time possess enough information, access to resources, and specialized education to "know" anything about why what we see in the night sky isn't what's really there from ALL perspectives. You want to feel superior so you frame it in your mind as this confounding discount scientific literacy level of common sense. But really, all the people you want to feel superior to just have lives that are happening much to quickly to care about your feelings or thoughts on anything. Let alone what concerns and upsets your delicate sense of reality self importance. I could be wrong. I'm not. But I could be.

[@Yakeru35]

No need to go on another planet to see different constellations, "just" travel to a country on the other hemisphere :)

[@rmsgrey]

Almost completely different, yes. If you're reasonably close, then looking directly toward, or directly away from, Earth, the constellations will look fairly similar - particularly looking toward Earth, where the stars will look dimmer and closer together (and there'll be at least one new star in the sky) but all the stars in that direction from Earth will also be in that direction from your new location.

[@renebrock4147]

Thank you, thank you. This has finally given me a coherent explanation for something I've experienced my whole life. Long story: when I was born, the doctor had to use forceps and clipped a muscle in my right eye. The resulting amblyopia was so severe they had to patch my left eye for the right eye to even develop. I was always looking through both eyes, but the eyes learned to move independent of each other if one was covered. Optometrists tell me this is not normal, but a coping mechanism my brain developed. However, the left eye remained very dominant until I lost most of the very central vision in the left eye to histoplasmosis at age 26. Only then did they discover I had pinprick scars all over both retinas, and that I had actually had histo since childhood. Not only did I have to teach the right eye to read, I had true binocular vision for the first time in my life. As a result of all this, most optical illusions have never been visible to me, including the Ames illusions. Looking at such things always gave me a headache which has always been a signal that something wasn't right in my worldview. Thank you.

[@silkwesir1444]

That I find unexpected. I would have thought, lacking stereo vision would make you even more susceptible to those illusions, not less.

[@Mindseas]

Sounds like you've been through a lot, and I appreciate that you share this! While it is hard to hear, it's also a fascinating example of the weird ways our brains can adapt, so thank you for that opportunity to co-learn from your experience ;)

[@renebrock4147]

@@silkwesir1444, I think possibly it is because I was never looking straight at something.

[@VeganSemihCyprus33]

A deadly illusion 👋🖐The Connections (2021) [short documentary] 💖🙌✌

[@renebrock4147]

@@VeganSemihCyprus33 Aside from running on several false assumptions (including the base one that humans and their creations are not part of the natural world), how is this germane to the topic at hand?

[@Brosephv]

The Ames Window always blows my mind. when the pen goes through the window, it's almost like a glitch in the matrix

[@VeganSemihCyprus33]

A deadly illusion 👋🖐👉The Connections (2021) [short documentary] 💖🙌✌

[@elainebelzDetroit]

And I found when I focused on one end of the pen, the window rotated correctly!

[@royalfelineandtracygrant]

@@elainebelzDetroitomg your right!

[@TamWam_]

Tbh I used the pen to help me see through the illusion lol. No matter how much I tried, I couldn't see the window rotate correctly til I focused on the pen

[@xeostube]

As a vision scientist, I think this was a pretty good coverage of these kinds of illusions and what they tell us about the human visual system. Well done, Joe.

[@Kartaal]

I'm a little surprised shadows weren't mentioned. Two objects of the same size, seemingly at the same 'height', can be mentally positioned either next to each other or along a diagonal line away from you based on whether their shadows are right underneath them or one of the objects appears to be 'floating' away from its shadow. And that's just for two objects that don't have shadows overlapping each other or other objects you can see in an open space. Shaded objects also do a ton to help you figure out distances, positions and sizes.

[@ginnyjollykidd]

That's exactly why the box was painted black and the chairs and chair illusion were on a black background. Oh, and the Ames window, too. But it didn't matter in person. Shadows, real or fake, screwed up my brain badly!

[@Emma-zc5jm]

Seems like the video focused on perceptive clues/rules rather than everything that affects visual perception like lighting and colour, as you mentioned with shadows.

[@VeganSemihCyprus33]

A deadly illusion 👋🖐👉The Connections (2021) [short documentary] 💖🙌✌

[@VeganSemihCyprus33]

Dominion (2018) 👀👍

[@TRUTHorSTFU]

Shadows? Well shadows are the absence of light so in actuality, they do not exist nor can they be seen because they cannot reflect light. lol

[@MoorganHart]

I’ve seen this subject done by some of the more physics oriented channels (e.g. Veritasium and Vsauce) before, but I liked getting Joe’s perspective on it. He definitely approaches it from a different angle. That being the biological factors which lead to one’s perception of illusions, rather than just the “coolness” and math. I used to think the fact that I couldn’t see illusions was another aspect of my mental disability (autism), but now I’m wondering if it means that my perception is better than normal? Maybe a trade off; better perception of reality at the cost of being able to relate to people. I compensate for my autism pretty well through memorization and understanding the things I don’t inherently perceive, so maybe it’s not actually a bad thing over all.

[@swedneck]

I wouldn't say it's better or strictly worse (obviously it kinda sucks to not be able to recognize emotions easily), just different. That's how i view most neurodivergence. The way it seems to me is that autism turns off a lot of image recognition stuff in the brain, so you're seeing a more raw, unfiltered view of the world, so to say. IIRC people with autism often describe that they see component parts of stuff they look at, rather than identifying them as a whole, is that correct? Like a face is two eyes, eyebrows, a nose, and a mouth, whereas a neurotypical person like me just sees a face as a whole, and it takes some concentration to look at each part separately.

[@VeganSemihCyprus33]

A deadly illusion 👋🖐👉The Connections (2021) [short documentary] 💖🙌✌

[@VeganSemihCyprus33]

Dominion (2018) 👀👍

[@AsmodeusMictian]

So, I'm curious. If you don't mind my asking, are you able to see ANY illusions at all, or is it just 'most' of them? This sort of thing floors me to think about, because we go about so much of our lives just assuming that the electrical signals that are hitting our grey matter are an accurate representation of our world. They aren't, at least not in the truest sense. It's just surreal to me I guess.

[@sidrykchewo]

We tend to believe that perspective is the way we perceive the world. But it’s a projection (technique) that matches our views, on a cultural and scientific level.

[@OleanderSmoothie]

Thank you for actually building each of the Ames illusions! Seeing a real, physical model is so much better than just a picture or digital animation!

[@kylefer]

Check out Veritasiums video on it.

[@Ottophil]

Temle grandin did it first!

[@chipersboy01]

I like the idea of someone ordering an Eames chair and then receiving the (significantly less practical) Ames chair instead.

[@besmart]

I hope this happens

[@micahbirdlover8152]

@@besmart I used to think 🤔 maybe I'm mind Warping 🤨🤭😀🤪

[@tiagotiagot]

The Ames Room illusion actually can still work with two eyes; I've been to a couple full sized ones, and with the right lighting and with the surfaces kept clean, you might still get the impression people on each corner are somehow the wrong size or change size as they walk across. The effect does break down if you move too much or if you're too close to the walls and stuff though.

[@Ewr42]

I mean, the fact that we can extract information from pixels and digitally generated sound waves is amazing In of itself already

[@TheLastCrow5150]

Multiple sclerosis started warping my senses and it got worse after the disease progressed. Psychadelic therapy has completely changed my primary visual cortex. Not only can I see better, my eyes interpret everything at a much higher level as well. Therapy permanently changed my vision. I prefer this to being blind

[@Tsskyx]

6:20 this is actually a historical misconception, medieval art wasn't like that because people didn't know how to draw, it was a preferred artistic style back then, sort of like with Corporate Memphis nowadays. It's distorted on purpose, to reveal more action, to allow for abstract symbolism, and so on. It is the difference between iconography and scenography, both serve their respective purposes.

[@TyrannoFan]

Thank you! I keep seeing this weird myth everywhere, and it always sounds like total nonsense. We have EYES for god's sake! People really think any human artist in the history of time couldn't just look at things to figure out how to draw in perspective? C'mon man. The context of artwork is important. I'm not a historian, but a loooot of art back then was in pottery and shaped objects. What use for perspective would they have in those mediums? It's no coincidence to me that perspective paintings became common when... well when paintings on flat surfaces involving geometric architecture became common?

[@AceSpadeThePikachu]

One of my favourite famous optical illusions in MC Escher's Endless Staircase. It works no matter what angle you look at it and whether you look at it with one or both eyes, because it plays with how the brain processes 2D images to try and create a 3D world. But since some images, like the endless staircase, are physically impossible in 3 dimensions, it makes the brain got "WTF?!"

[@tylermacdonald8924]

Did anyone else as a kid just lay in bed maybe early in the morning and imagine spaces so huge you had to stop imagining because the expanse felt so huge? These optical illusions remind me of these vivid scenes

[@SeaTacDelta]

13:40 Dr Becky did a fantastic representation of Orion in her office a while back. It's amazing to see such a common sight from a different perspective.

[@zakyzigzag]

It's always amazing the fact that mirrors and other flat, reflective surfaces also reflect depth

[@cocobeans3742]

As a person that sees (mostly) out of one eye, I can tell you there is a difference between watching a screen and real life. I don’t see in full three dimensions, but because of the cues the brain picks up I think I see way closer to 3d than 2d. Thank you brain

[@Mindseas]

This was great, because it isn't just "look at these cool illusions, lets figure out how they work"! It's funny to see how unreliable our ability to perceive things is, and maybe would've been worth mentioning not only does our perception rely on educated guesses, it's also always behind reality, so we technically cannot live in the now in terms of our senses. I think the distance illusion with the two dots or circles suffers a little from the camera focus, because you can tell the right side is closer by just looking at how detailed the surface is. Granted that's much easier to do afterwards when you know what it's about. The Ames' window is still really funky to look at, even after seeing this and the Veritasium video on it, it seems unreal that it's persistent and takes quite a bit of effort to override the automatic error correction to actually see the motion as it truly is. Fascinating stuff!

[@SgtSupaman]

As was pointed out near the end of the video, our perception is actually very reliable. These tricks only work from an extremely limited point. It seems impossibly magic through a camera, but our eyes in real life will see through many of these without issue.

[@OldmanNix]

This goes to show, digging your heels in the sand and not changing your focal point of view isn't healthy and you can be thus be fooled easily. So stay flexible people and "look" at things from different angles and only then make up your mind. :)

[@STRUCENGG]

the amount of effort in making this video is amazing👏

[@lesleyghostdragon3149]

It's no illusion that this is one of the best (concise, informative, and fun) science shows available! Thank you for helping us "Be Smart" 🤓 Staying curious 🖖

[@chrisg3030]

As the 15th century wore on, not only did art go from looking like this (6:19) to this (6:21), but also the solar system went from looking earth centered to sun centered, once the Ames window-like illusion of planetary retrograde motion had been figured out by Copernicus.

[@didack1419]

That's an interesting realisation

[@ellepalmer4590]

When you mention the two eye trick, I have that, but most of the time my brain doesn’t know which one to use do I always see both. It does this because I have an astigmatism in my left eye. It learned to ignore it. WoW. But now my brain has to learn it that it is getting correction from my glasses.

[@chrisg3030]

One of the eeriest and yet most frequent illusions is when you go past an airport in a car or train and see a plane apparently hanging motionless in the air.

[@SlowToe]

I perceive this channel as excellent no matter what the circumstance.

[@jacksoncross9265]

bro hes so great too

[@makoyoverfelt3320]

I'm really glad that the last several videos from this channel feel like they've come back to the original spirit of the channel. Keep making great, educational, and entertaining videos!

[@Johny40Se7en]

What an absolutely wonderful and thought provoking video, and it's also why a lot of magicians' illusions works so well 🥰😊😄 I've always been quite fascinated with the kaleidoscopes you use when you're a kid too 😉 Cool stuff.

[@VeganSemihCyprus33]

A deadly illusion 👋🖐👉The Connections (2021) [short documentary] 💖🙌✌

[@SilverAura]

The Connectivity illusion hits me the hardest as someone who frequently creates 3D assets. You almost have to keep your attention split between multiple point of views to avoid creating these illusions on accident. Depth perception is the one thing I was excited to gain from in 3D monitors, but that market went bust.

[@riddhichakraborty4890]

"Very different people see/perceive the world the same way." WOAH. It is a powerful thing to say. Thanks Dr Joe for making this video. PS: the joke about Orion was good😂😂

[@AlphasysNl]

Is it really true though? I would agree with shapes, but what you see as red, and thus call red, I will also call red, but might give me the sensation of your green.

[@VeganSemihCyprus33]

A deadly illusion 👋🖐👉The Connections (2021) [short documentary] 💖🙌✌

[@daveyc02909]

@@AlphasysNl Wouldn't that just mean that you call the same visual phenomenon (the color) by different names (so still seeing the same thing)? I think the fact that some can't see a given color is more of a counter example

[@chrisg3030]

That Orion joke reminds me of another KZbinr (I think it was Dr Becky) saying that some galaxies look Messier than others. Groan.

[@funkyskitchen]

I think those Magic Eye pictures from the 80s and 90s are another great example about how sometimes info can be shoehorned into our perception.

[@Credlich05]

i was waiting for the video to mention depth perception, it was something i was born without because i can only ever use one eye at a time

[@ketsuekikumori9145]

Speaking of constellations. What are the most consistently used stars across cultures? I'd imagine the north star, the southern cross, orion's belt are pretty universally recognizable, but are probably grouped with different set of stars depending on the cultures' constellations. Take the north star for example. It is usually grouped together with the Big Dipper and/or Ursa Major, with Ursa Major taking the Big Dipper and adding more stars to make the bear's body.

[@NakedSageAstrology]

The most common are shared among the 28 constellations attributed to every major culture & their study of SpaceTime. Jyotish, Vedic or Indian Astrology- makes use of the 27 Nakshatras & you will find the Codex of This Celestial Dream within its mansions. If you want to know the Secrets of This Youniverse, *RorriMaesu says useaMirroR*

[@ObjectsInMotion]

Remember the North star changes as the earth slowly precesses on its axis, 3000 years ago the north star wasn't polaris, and famous stars like Deneb and Vega have even been the north star before!

[@georganatoly6646]

as a software engineer makes me wonder how effectively these perspective hints can be quantified and incorporated into something like the software that parses image files generated from a camera for image based AI, being able to cull large amounts of data based on these hints might be an effective way to reduce the number of objects the AI has to interpret, assuming the implementation of the culler didn't prevent the AI from hitting its hard real-time requirements, obviously there has to be some set of existing object culling algorithms in image based AI already, wonder if any directly use techniques like this, I would assume they'd have to be relatively simply and thus efficient based on the fact that they're 'cognitively impenetrable,' but then again maybe that's like saying, 'because I can't choose to see something as green instead of red it then must be easy to distinguish color' -- anyway...

[@nickadams9504]

Machine Learning for images mostly use CNN (convolutional neural networks) but they could also use just a dense NN. The training time on a dense neural network for images is insane though especially when considering lots of images. That being said in a way they are being trained on these "rules" of reality in a sense as we feed them images with perspective typically. Something else interesting is you can have separate hidden layers learning features of a specific subject. For example, a dog can be broken down into limbs, ears, face, and etc that way if you just see ears in an image and nothing else it can still classify them as dog or not dog. In this way the model is constructing an object in reality from more ambiguous sub parts. It's really cool stuff you can even use this approach with a GAN which was displayed by NVidia recently to do image editing, transformation, or just creating whole new objects from what it learned and constructing the image out of its sub parts.

[@bumblebeegamerreal]

Its been a while since you posted, and I gotta say that this video is worth watching

[@martti1190]

But you haven't watched it yet... The video came 18 minutes ago and you commented 15 minutes ago. Stop farming for likes

[@Jskid666]

@@martti1190 bruh, 2x speed is a thing... Stop assuming the worst in people.

[@martti1190]

@@Jskid666 The video is 20 minutes long with 2x speed the video is 10 minutes long. And he posted the comment 3 minutes after the video came out. There isn't any way he could've watched the video in 3 minutes. So no, I'm not assuming, I'm stating a fact

[@randomheliumball7505]

@@martti1190 lol true

[@randomheliumball7505]

@@Jskid666 but why would they watch it in 2x speed I mean the explanation isn't clear and it's literally pointless

[@readwithhaziq]

Indeed your channel is one of the best educational channel in the world. I have watched all your videos and I love them. In fact I started watching your videos when I was 12years old through TV channels. Those times I did not know English but I used to watche them in persian. Lots of love and respect

[@daveking3494]

Exactly the same thing happens with our hearing as well. In music, if you just hear a C major chord, you assume it’s a piece in C Major. but depending on the context of the music following it, the piece might actually be in G Major, or F major. This is common knowledge, among musicians and composers. It has been used for hundreds of years to fool the listener, which makes the music more interesting! You could do a whole program on how our ears fool us as well.

[@rb.arindam]

That window, seen it first in Veritasium’s video. It broke my brain for a good couple hours. Today when I saw it again, I was able to tell it was rotating clock-wise viewed from top. Which your hand gestures later showed to be accurate. And it became lot more clear when you put that blue stick on it. Last time that felt like a nuclear weapon thrown in my brain. It's still a little fuzzy when the shorter edge is at my closest, but overall I was better at seeing it.

[@chrisg3030]

15:43 "One of the strange things about most of Ames' illusions is most of them only work with one eye from a very specific spot, which is why so many of them work so well in video". But there's one rotation illusion you can see with both eyes in 3d reality from a locus of positions. A two bladed wind turbine when seen off to one side will appear to rotate jerkily, but smoothly when viewed head on. The best explanation I can think of is that the circle traced out by the blade tips will foreshorten (or perhaps "forenarrow") to an ellipse when viewed from an angle. The tip of a blade has less apparent distance to cover when approaching and leaving the vertex (pointy end) of the ellipse and will thus appear to slow down to compensate, and correspondingly speed up when passing through the co-vertex (flatter bit at the side). KZbin has some examples of two-bladers, but go visit in person if there are any near you.

[@chrisg3030]

So what's the brain doing here? Does it deliberately slow down the blade tips in order to keep phase with them?

[@Ewr42]

a cool illusion I like, is to look at the Arc of the milky way, then tilting your head to the side and realizing it's a straight line. also works on sunsets for those that don't have a clear view of the night sky

[@AvroBellow]

There's a gigantic mural in downtown Montreal on the Mission Old Brewery. The artist was an absolute genius because it looks 3D. It looks like the Montreal Metro is coming towards you from far away. When I show it to people, I blow their minds by pointing out that it's a 2D image on a flat wall. The mural itself is about 50' tall so I shudder to think about how long it took to paint it.

[@ingridfong-daley5899]

I experienced a traumatic brain injury in 2017, losing my identity, about 10 years of my life, certain language abilities, and, interestingly, a shift in my visual processing of illusions. Rather than seeing one illusion or the other, i now see all permutations/angles simultaneously. IDK if it's exactly related, but post-TBI I also gained math and science skills i hadn't had before--like I now see/think in geometric pictures rather than linear constructs. I keep wishing a neuroscientist would take me on as a guinea pig to explain more about it.

[@waynedarronwalls6468]

Always loved the Belvedere Impossible Building...it's just so counterintuitive when you look at it really closely.

[@shardinhand1243]

i love how ilusions can mess with sight, our brains interpret signals in a predictal way and knowing that way means some interesting tricks can be done like on demand hilusinations from patterns that mess with our brains ability to recognize paterns and stimulass.

[@ReiDaTecnologia]

The most incredible part is that the brain do all this process in milliseconds for each frame while also taking care of the rest of the body's functions, shows how powerful the brain is.

[@cckenforcer]

I watch Veritasium’s video on the window illusion 1 year ago and couldn’t see it at all, but now i can and can’t unsee it.

[@roderick.t]

The light scattering from the atmosphere near the Earth’s surface is also a visual cue that we all use. In the daytime, objects that are further away appear ‘brighter’ due to more air particles that scatter the light compared to objects closer to us - a subtle effect our brains grow accustomed to. On the moon, there’s no atmosphere, and the astronauts frequently misjudge not only the distance to an object but also its physical size.

[@nightthought2497]

The Ames window is not cognitively impenetrable. There is a subtle clue, that once identified, breaks the pattern. Now, most Ames windows have a characteristic curve, due to the nature of their construction which gives it away, but even in a perfectly constructed Ames window, the "far" end changes size dramatically compared to the "near" end. Once that feature is identified, it is exceedingly difficult to shift back into the illusory frame. The Ames room is perfect due to the stationary state of the illusion generating space. But the moment you add true motion to an illusion based on depth perception, several nuances of motion perception add new features the can break the illusion.

[@Ulthar_Cat]

There is art thousands of years older than the european renaissance that has complex perspective 💜

[@Beryllahawk]

Fun video!! I hadn't realized that Mister Ames did ALL those different illusions. I've seen the Ames room and the Ames chair before - but the window was a new one to me! And it made my eyes feel like they were gonna cramp, haha Brains are incredible, and the more we learn about them the more incredible they seem! Great video!!

[@luismijangos7844]

Excellent video Dr. Joe. You made a lot of work for the illusions. I appreciate it.

[@Morbazan125]

They show me how easily we can be manipulated on such a simple level that it’s scary to think what other ways are we deceived

[@ryvyr]

Super appreciated as always, especialy having non-adsense at end or beginning rather than interrupting videl. It makes such a difference, more than brief words do justice. As for RealEngineering, unfortunately his FUD on solar/wind and push for hydrogen and partnership with Toyota means no support for myself and like minds.

[@Rabano_Yodado]

What You said at the end, before the ads, was amazing

[@karamimamali6139]

it's first time that I see this channel , it's really good

[@donaldinnewmexico]

RABBIT HOLE!!!

[@micahbirdlover8152]

mine too😊

[@hideninja1546]

When I was young I used to do it for fun because it was beautiful to watch in my eyes

[@nadionmediagroup]

It’s a visual heuristic. A set of “rules” that’s close enough for our needs. It’s only technology that has revealed this. Our ability to see is now augmented.

[@Marandahir]

This is why they could film Lord of the Rings with anamorphic sets and foreshortening designs to achieve the size differentials between Gandalf & the Hobbits, but when they filmed The Hobbit with 3D cameras, they had to use different techniques to achieve the same height differentials - such as constructing two parallel sets at different scales and digitally fusing them in post-production, or else by filming them together but during post, digitally cutting Gandalf out, increasing his size, and pasting him back in.

[@--Paws--]

That kindergarten drawing analogy says a lot, I feel like this should be a course in some art classes, specifically that analogy.

[@greg-op2jh]

I'm epileptic and believe me when I do have a seizure my spatial perception gets all f'd up. It is very important!

[@GTAVictor9128]

Another optical illusion worth mentioning are the sports adverts, namely in football. It always gets me how these "billboards" appear 3D until a player steps on them to reveal they're completely flat.

[@venividdivici0]

would love to see more of this 👏🏼

[@elisa.llew-send]

Loved the John Green shout out and the library nod was excellent

[@DuskPixel]

This was one of the most interesting videos I’ve ever seen! Thanks for notifying us about this issue.

[@nariu7times328]

Love that you build the chair one!

[@Crazyone419]

This is one of the best videos I've ever seen!! Thank you, and I subscribed!!!

[@m3gduwu560]

idk if you can't do anything about optical illusions, for example I'm pretty good at choosing wich way the spinny ones go and with the one you showed I was able to actually tell wich way it was spinning after having seen wich way the arrow on the bottom spun

[@jacksoncross9265]

can we all take a moment to thank our host lol hes awesome

[@cookiebinary]

Good video for kids. They will understand the basics.

[@julianschwertzthewoodlands4161]

1:56 You got me good here....love this type of illusion!

[@lizellafernando1780]

I love how he edits in the greenscreen instead of the other way around

[@ginnyjollykidd]

I've seen an Ames window in person using both eyes, and I _still_ couldn't figure out how it was turning! The shadow of a ballerina turning? I can perceive it clockwise, counterclockwise, and oscillating alternately with little effort. But the Ames window completely baffles my brain.

[@eileennono5039]

The Sugihara illusions are a great example of "this makes my head hurt" as well.

[@TheSkystrider]

The fact of how powerful stereoscopic vision is, has absolutely blown my mind why 3D TVs have failed. 3D video is 1000x more pleasurable and realistic than regular. I can't comprehend why anyone would ever want to watch without stereo vision!🤦‍♂️

[@kaitlyn__L]

The reason I don’t like it is because there is a disconnect, between the different images my brain is receiving and the fact I can feel my eyes are not focusing or moving (as the video discusses with the marker pens segment) off of the screen, which can make me feel sick or get a migraine because of that conflicting signal. A true volumetric display wouldn’t have this problem, and I love looking at holograms, but a flat screen simulating depth with two separate images will _always_ have this problem. I’m sure 3D is the future, but true 3D rather than simulated 3D - a screen with the depth perception and moving field of view, just like you have when looking out the window. However, artistically, that does have its own concerns - almost all cinematographic techniques rely on careful framing and movement of the camera, which such a screen would interfere with. On the other hand, it would be really good for live sports and video games.

[@martinomasolo8833]

It was a joy to see you play with these illusions (and with our minds😂)

[@RythmGkwd]

Was the channel's name changed from "It's okay to be smart" to "be smart" or I'm having a Berenstain/Mandela moment

[@burgercide]

It's smart to be smart.

[@rhouser1280]

16:36 I've never "seen" this one before, it was pretty cool!

[@bobtuckey2409]

Very cool Joe! A fascinating topic.

[@InimicusSolitus]

This got me thinking. When measurements are taken at the quantum level, are we looking with "one eye", and missing vital information we just can't detect, and that is why Quantum Mechanics seems so weird..?

[@wolfbro82]

I had a very hard time learning to read as a kid. I remember the first book I ever loved was all about visual illusions. OPT

[@premnaren8675]

That was one of the coolest intros ever! AWESOME

[@TheMrCougarful]

This reminded me that most people today do not get the chance to see a night sky full of stars.

[@Warekiwi]

Excellent video and helps to explain the huge task that Tesla engineers have in trying to interpret the real world situation from 8 cameras with the eventual aim of achieving "full self driving"!

[@basil127]

0:55 it was green screen all along?

[@besmart]

😎 yep

[@spoicat5459]

Smart

[@randomheliumball7505]

Smartly smart

[@micahbirdlover8152]

a big mess funny 🤭😄

[@micahbirdlover8152]

@@besmart I really love your videos 😉 I'm nerd for it🤓 there 😊

[@dhindaravrel8712]

Good ways to determine what's real and what isn't are common sense and using other senses to get additional information. With more difficult problems, scientific instruments. Failing all three at the same time is called having a religious experience.

[@grahamnewton4381]

You brain also constructs what you think you hear. Tell something to a group of people and they will interpret the words differently focusing on certain things and ignoring or even not ‘hearing’ others so they will go away with different messages.

[@safaiaryu12]

So due to some medical shenanigans, I only really use one eye even though both work. My depth perception isn't great, but I'm good at these clues you're talking about like relative size, blurriness, and perspective. Oddly, when I was in art classes, I picked up one, two, and three point perspective faster than anyone else, and I think it was exactly because I have no natural depth perception.

[@tmrogers87]

This seems like it was a really fun video to make. Thanks

[@trinab.787]

I love all of the models you made for this

[@braydonattoe2078]

Scientists are discovering nutty things about how we perceive reality, kinda mind blowing how much our minds guess images and just paste it in without conscious effort

[@timfriday9106]

thats why so many shooters argue about whether you should look through a sight/scope with 1 eye or 2.

[@diffcontroversy]

Love this show, but there were 9 ads. 9! That's insane.

[@AnimilesYT]

When humans get presented with the same information we'll usually come to different conclusions. But this is because most of the time it is heavily influenced by things we've experienced or learned before. So we actually aren't presented with the same information. We're actually presented with another addition to our information :)

[@tentanghukumkita6381]

8 Illusions That Explain How You Create Reality Very interesting and helpful explanation ❤️

[@donevans1884]

what a brilliant video , it really makes you think , thank you .

[@IssaalaaRacing]

One thing that has always perplexed me is whether different people see color differently

[@braydonattoe2078]

Dude I've thought this for years. Like what if everyones colors were slightly shifted so like I see what I know as red and you know as red, but if i took that information from my brain you're brain would see it as orange or yellow. I've thought about it for so many years that i feel its definitely possible. As long as the shifts are along the natural gradient and whatnot, it would still work even when you start to get into colorblindness and stuff

[@braydonattoe2078]

One more thing I forgot to mention is favorite color... like what if everyones favorite color was actually the same but we all see and know it slightly different

[@Kenkire]

I love this kind of stuff. As an aside... 18:33 Anyone else thinking he was going to poke himself in the face?