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A Magician Explains Why We See What’s Not There
- bobosha 8y agoThe neuroscience explanation for this is "Predictive coding". These talks are fascinating. related: https://www.youtube.com/watch?v=CvAbPtbjxhw&t=1135s https://www.youtube.com/watch?v=CvAbPtbjxhw&t=1135s https://www.youtube.com/watch?v=P0yVuoATjzs https://www.youtube.com/watch?v=P0yVuoATjzs
- escherplex 8y agoRight. So there is a received cognitive operating system which generates an interactive model of 'reality' shaped by historic experience, a facet of this system involves 'hierarchical predictive coding.' When parsing percepts, this subsystem front-loads what aspects of a new experience of interest to accept and what to ignore based on shaping from past experience. A simple example: promise a child a quarter if the correct hand is chosen. Place quarter in right hand then fold fingers up, occluding quarter. Appear to grab coin with left hand, quickly close both hands, and present both fists to child then ask 'which hand holds the quarter?'. Based on past experience it would appear that just a transfer of an object from one hand to another took place so child selects the empty left hand. Then immediately rerun the same test with the new experiential history encoded and find the child (usually with a smirk) chooses the right hand (assuming you didn't pocket the coin to further confuse the child).
- bobbiechen 8y agoCool videos! A nice written introduction to the topic of predictive coding is Scott Alexander's book review of "Surfing Uncertainty" by Andy Clark: https://slatestarcodex.com/2017/09/05/book-review-surfing-uncertainty/ https://slatestarcodex.com/2017/09/05/book-review-surfing-un...
- skosch 8y agoI have found that book to be an impressive example of poor scientific writing – one long, convoluted, intentionally obtuse sentence after another, as if the author was constantly trying to make the reader feel like an idiot. I have found some more technical articles (e.g. [0]) very useful, but if anyone knows of a comprehensive introduction that takes more of an experimental psychology angle, similar to Surfing Uncertainty but less frustrating, I definitely want to know about it. [0] https://www.sciencedirect.com/science/article/pii/S0022249615000759 https://www.sciencedirect.com/science/article/pii/S002224961...
- empath75 8y agoI got bored a couple of years ago and decided to start learning some magic. If anyone wants to learn card magic, there are an unbelievable amount of tutorials on YouTube. All you need to do some very impressive tricks is a single move — the double lift.
- hentrep 8y agoCan you link to some of your favorites?
- dkersten 8y agoI started learning myself in late November 2017. You can get a LOT of mileage off a $10ish book too (eg “expert card technique” or “royal road to card magic”[1]) But yes, I follow a few YouTube channels that have taught me a lot: Xavier Spade, Alex Pandrea, PigCake and a few others. There are some excellent ones, but I noticed that you do have to be careful, there's a lot of "reveals" or "tutorials" that are done by hobbyists and their quality is varied, some would teach bad handling or bad habits. They can be fine to get the concept, but maybe not as an absolute beginner. The ones done by magicians who perform professionally tend to be great quality though. But you probably know this better than I, since it sounds like you've been doing it longer :) Its really easy to find tutorials and guides nowadays, you just gotta put the time in! I personally don’t actually like the double lift because I find that 90% of them, even though they are perfectly executed, just don’t look natural — most laypeople simply would never turn cards over in the way most magicians do and it just looks fishy. Having said that, most laypeople don’t actually notice (it’s ibcredible what you can get away with sometimes!) but I notice it and it puts me off :) [1] A side story on this book... I may have cost the publisher a bit of money... They have a "video edition" of the book, where many of the techniques and routines have a QR code linking to a video, but when I got it, all of the links were broken. So I complained to the Advertising Standards Authority (UK) and about two months later, all of the QR codes started working. I noticed that they all directly linked to Rackspace CDN URLs (ie not to their own domain). I can't imagine it was fun or cheap to get the exact same identical URLs working again...
- gregorygoc 8y agoI’ve been doing magic half professionally on and off for almost a decade now. Basically, I don’t do card tricks anymore and the reason is simple - if you were to do real magic, would you do it with playing cards? On a side note, revealed card tricks on YouTube were my pain in the butt for a long time, but I don’t care anymore.
- PavlikPaja 8y agoOne must always marvel at the mental gymnastics neurotypical people go to to explain why their hallucinations are actually a good thing.
- wlib 8y agoImplying that said hallucinations, tailored by evolution, are actually a bad thing.
- PavlikPaja 8y agoPeople outside the WEIRD (Western, Educated, Industrialized, Rich, Democratic) populations don't experience them. They are not shaped by evolution, but likely by the excess iron in western food that gets into the brain and shifts the brain chemistry towards a psychosis like state. (you can look up studies on rats, or I can look up some if you want) People who are immune to it have Asperger's or something similar "on the spectrum". Anyway, here is one: https://www.ncbi.nlm.nih.gov/pubmed/6138953 https://www.ncbi.nlm.nih.gov/pubmed/6138953
- mrunkel 8y agoI'm totally shocked that a wacky theory proponent (complete with zany acronym!) would link an article talking about iron deficiency to promote their wacky theory that excess iron causes a psychosis like state.
- PavlikPaja 8y agoThat acronym is well established in psychology.
- wdutch 8y ago> What this shows is that participants used my face to predict where I would throw the ball Being someone who likes to avoid eye contact, this explains why when I'm walking I always end up doing the get-past-you shuffle.
- asadjb 8y agoI had; and to a certain degree, still have this issue. But I got my rate of doing the "get-past-you shuffle" down quite a bit after learning a simple trick. While I avoid eye contact, most people do not. Most people, when they see an on-coming person, judge which side (left/right) to pass them by looking at their gaze. The trick is to look in the direction you want to pass the other person in. So if you're going to take the left side, look to your left. Most people will then pass you on your right side.
- failrate 8y agoYep, head facing is maybe even better than eye contact. In addition, local road rules even out the rest (e.g. which side of the road do people drive on in the country where you are currently walking).
- eridius 8y agoDefinitely head facing. If I'm anticipating a collision, I generally turn my head slightly in the direction I'm going even if I don't move my eyes. I think of it like my nose is pointing to the side I'm going.
- feintruled 8y agoAnother good technique is to commit to avoidance early, and stick to it. For example, when you notice the collision course, start bearing left immediately - the other person may have started to move in that direction, which would normally start the 'shuffle' as you both shift to your right, but you short-circuit that by not reciprocating - keep left. Seems like it might be rude, but in practice it doesn't seem so, the relief outweighs any ill feeling (or so I imagine!)
- Sam_Harris 8y agopaywall
- have_faith 8y agoThe next stage from this is how a spectator remembers a magic trick later on. Good magicians work backwards from this understanding in designing an act or trick. "He put the card in the middle of the deck, and it appeared in his pocket". This is about as granular as the average spectator remembers a magic trick only minutes or even seconds later. It says a lot about how lossy our memory really is even when we are concentrating our hardest. Maybe counter intuitively the harder someone looks the easier it is to direct their attention. I would recommend anyone learn a simple magic trick or two, if only to help you design your products better. All of the information you learn about how people move through the phases of a trick seem transferable to lots of disciplines.
- dkersten 8y agoI remember a magician talking about a particular routine where he did everything, but when the spectators later retold it, they felt like they did it (eg: "I took a card and then..." when in reality the magician gave them the card, something like that anyway). I started reading the book "Sleights of Mind"[1] a while back, I need to go back and finish it. It talks about this subject in depth. I performed a simple trick for a friend once and then, maybe an hour later, another friend arrived so I performed it for him too. The trick involved swapping something out and doing some very basic sleights to hide the fact that it was swapped. My first friend was watching, knowing the outcome, trying to figure out at what point I swapped, but he didn't spot it. He later asked me "did you swap it before or after X", which I found interesting, because all of the work was done long before X. I love the tricks where the trickery gets done early on and then its just theatrics before the reveal. It really makes it hard for spectators to piece together the events. :) [1] "Sleights of Mind: What the neuroscience of magic reveals about our brains" -- http://www.sleightsofmind.com/ http://www.sleightsofmind.com/
- klenwell 8y agoOn this topic, one of my favorite HN comments compares magic tricks to hacking someone's brain: Magic tricks are hacking! You are hacking someone's mind, particularly their assumptions and attention. The exploits to human psychology and attention are just as sure as the exploits to crack or unlock a smartphone and many other software exploits. The difference is that software can be patched but the evolved behaviors that are the root of the exploits used by magicians are very hard to "patch"... Full comment: https://news.ycombinator.com/item?id=4992826 https://news.ycombinator.com/item?id=4992826
- tyingq 8y ago"simply looking at the ball. This, however, was not the case: Although they looked at the ball once it had been thrown in the air, they spent a lot of time looking at my face, particularly before the ball reached the top of the screen." I wonder if self driving car tech thinks about this kind of thing. How often, for example, at intersections, we look at the faces of other drivers and pedestrians for context. It's interesting to me both as data for the self driving car, and the obvious lack of data for human drivers looking at a self driving car.
- fjfaase 8y agoIt is my experience that I often know what a driver before me is going to do even before they have started to do so. Probably because I pick up very small changes in their behavior, as like reducing their speed a little, even before I have become conscious of them doing so. In theory you could train a neural network to do the same, but it would probably require a neural network much larger than the 'electronic' ones that are being used. I guess our 'biological' neural networks are still much more efficient, energy and size wise, than there 'electronic' versions.
- InitialLastName 8y agoI'm not saying it is, and I'm not saying it isn't, and I definitely have felt the same thing, but it seems to me that the sensation you're calling out is very susceptible to both confirmation bias and post-hoc reasoning. For example, I'm sure your brain fires harder when your "expectation" is met than when it isn't or in all those situations where you just don't make a distinct prediction.
- greenhatman 8y agoMy feeling is that AI would be able to do this much better and more consistently than humans in a relatively short amount of training time. Provided that for instance all Teslas can learn from all other Teslas' experience.
- falsedan 8y agoWhen teaching my kids to cross the road, I tell them to look for oncoming cars and to make sure the driver can see them (by checking where they're looking) instead of trying to judge if there's sufficient space to cross safely.
- blancheneige 8y agoThis reminds me of an old legend (probably made up but what do I know) that when early European explorers first reached North America, some native American tribes, then settled on the shore, were unable to see the ships coming on the horizon, until one of their shamans pointed at them, because only they had the necessary conditioning and open mindedness to perceive and anticipate things that were unfathomable to others.
- krapp 8y agoI'm 100% certain that didn't happen, and /r/askhistorians seems to agree[0]. Humans just don't work that way. [0]https://old.reddit.com/r/AskHistorians/comments/3lh0kz/is_it_true_that_when_the_indians_saw_ships_for/ https://old.reddit.com/r/AskHistorians/comments/3lh0kz/is_it...
- blancheneige 8y agoThanks for the link. Sounded a bit hard to believe indeed (although if it were true it would more likely come from Native American folklore rather than the other side, for I can hardly imagine how they'd be able to recollect that story from their viewpoint).
- libertas 8y agoI remember seeing that in a documentary about perception "WHat the bleep do we know?". I might have found some original reference at some point in a book about Magellan arriving for the first time at Tierra del Fuego. I don't remember the details.
- libertas 8y agoI see what I know I see what I know I can see
- winchling 8y agoWe don't really 'see' things. Rather our eyes are just one of the means by which we correct our guesses about what's out there.
- csmeder 8y agoIn the field of UX/Psychology there is a term “suffice”. Our brains are constantly sufficing rather that perceiving all data and interpretating it. If we had to do the latter end of the spectrum, our heads would need to be bigger, to the point birth wouldn’t be possible based on current female autonomy. You wouldn’t have survived child birth. As a result when a person visits a page on a website for the first time people in average scan the page only reading a few words (I’ve hear 7 on average claimed). However, most beginner designers will not realize this and put a couple hundred words on a page with out proper typographic hierarchy. Better designers (same is true for poster designers) use typography and visual hierarchy (Font sizing, spacing/white-space, color, font weight, alignment) to create a design that is easy to scan for a sufficing human brain. The less scannable the page is the more the brain needs to work to make sense of what is being displayed (higher cognitive load), and the less of a chance the user will read the highest priority data first (the context or hook data). If the user reads the data in the wrong order, it will likely be confusing noise. The goal of a designer is to present the data in such a way that the signal to nose ratio is high, as they scan and dig deeper into a presented page or poster.
- pier25 8y agoI've always said that the most important job of a UI designer (or graphic designer in the case of posters) is how you communicate with your users. Unfortunately it's too common that people, specially designers, put aesthetics first. To put it bluntly, users don't care about the drop shadow of a button if they can't find the damn button or if they don't understand in advance what the button will do.
- DINKDINK 8y ago>the most important job of a UI designer [...] is how you communicate with your users. >[...] it's too common that people [...] put aesthetics first. While aesthetics don't need to come first in a design, they do allow a large amount of information -- that you're trying to communicate -- to be encoded in a way that's processed subconsciously and quickly: A stranger dressed in "war paint" approaches you to sell you a coffee is going to perform worse than a Nanny wearing a warm, fuzzy, cozy, looking sweater.
- falsedan 8y ago> One of my other truly astonishing skills involves throwing a ball one meter into the air and catching it. A true miracle of coordinated tracking, movement, and prediction. I'm delighted to see such a seemingly-trivial thing called out as the remarkable feat it is. If you feel it is quite mundane, consider how much work it would be to automate.
- cr0sh 8y agoHe mentions people looking at his face to aid in predicting what the ball's trajectory will be. I wonder what eye tracking data from those with high-functioning autism (or whatever they call what we used to call Aspergers) would reveal, since "face blindness" and the inability to interpret facial expressions are typical hallmarks in those individuals? That is, do such individuals experience a degradation in coordination in such tasks, and/or related tasks, due to such inabilities? Or do they make up for it in other ways?
- syn0byte 8y agoThe example of Agnosia cited in the article indicates that there wouldn't be any degradation. Proprioception and physical interaction seem to have their own dedicated pathway. If not being able to tell vertical from horizontal didn't affect the patient's ability to interact with the world, why would not being able to tell if a face is "happy" or "sad" have an impact?
- darkerside 8y agohttps://www.youtube.com/watch?v=6YIPtJlCbIA https://www.youtube.com/watch?v=6YIPtJlCbIA Here's the hollow mask illusion, one of the most fascinating parts of the article for me.
- eridius 8y agoMy favorite part of that is the fact that the perception of the hollow mask rotates in the opposite direction as the actual hollow mask does.