yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Tangram Paradoxes


less than 1m read
·Nov 10, 2024

I can take the seven pieces of a tangram and arrange them into a shape called the monk, but I can take the same seven pieces and arrange them into a monk with no feet.

Wait, what? Where'd the foot go? How can these be made of the same pieces? Is it magic? No, it's a Tang G Paradox, which is a kind of dissection fallacy.

In my Bonet Tarski video, I showed an example where we fail to notice how the parts have changed, so we're surprised when the whole does. But in this kind, we fail to notice exactly how the whole has changed, so we're surprised to find that the parts haven't.

Illusions like these are caused by the fact that a concentrated area of missing material is much more noticeable than an equal but diffused increase everywhere else that compensates for it.

Both of these figures have the same area. The one with no feet has a slightly larger body, but the area of just the feet spread out amongst an entire arrangement... well, it's kind of hard to see.

Sometimes the things we don't notice can be quite significant.

More Articles

View All
Khan for Educators: Our Content
Hi, I’m Megan from Khan Academy, and I’m here to share more about the content available on Khan Academy. When we talk about content on Khan Academy, what we really mean is all the videos, articles, and practice questions that learners interact with. We t…
Virtually Viral | Explorers in the Field
(Gentle music) [Pardis] Early on when my research wasn’t going that well, and I was having trouble, people would be like, well, she’s in a band. But then when my research started going well, and I started publishing, they’d be like wow, and she’s in a ba…
A Former FBI Agent Explains the Terrorist Watch List | Explorer
What exactly can the government do to him, to any of us, whether we’re on the watch list or not? As a journalist, my first hunch is to go straight to the source. Michael German is a former FBI agent who has experience with the terrorism watch list. What …
Proof of the derivative of cos(x) | Derivative rules | AP Calculus AB | Khan Academy
What I’m going to do in this video is make a visual argument as to why the derivative with respect to X of cosine of x is equal to sin of X. We’re going to base this argument on a previous proof we made that the derivative with respect to X of sin of X is…
Inside a Kangaroo Pouch - Smarter Every Day 139
Hey, it’s me Destin, welcome back to Smarter Every Day. Simple question here. Do you know, like really know, what a kangaroo pouch looks like? Several years ago, I was invited to Australia to help promote National Science Week with my friend Chris, who ha…
A Tale of Two Atoms | Cosmos: Possible Worlds
The writer H.G. Wells, who first imagined time machines and alien invasions, had a nightmare of a future world where atoms were weaponized. In his book called “The World Set Free”, written in 1913, he coined the phrase atomic bombs and loosed them on help…