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
The brain's hidden superpower
Let me know if you’ve ever been in this situation: you’re sitting down writing something, and you’ve been struggling for hours trying to find the right words. It’s super painful and frustrating, and no good ideas are coming to your head. But all of a sudd…
Trying to Catch a Coyote | Live Free or Die
Cole Bert’s property taxes have spiked during his worst trapping season on record. A quail plantation looking to get rid of predatory coyotes is his chance to score some high-priced pelts. It’s a win-win situation because they get rid of their coyotes so …
For parents: Setting a daily learning schedule for middle school students
Hello all and welcome to Khan Academy for Parents 6th through 8th Grade Remote Learning Webinar. I’m Megan Patani, I lead U.S. Professional Learning here at Khan Academy, and I’m joined today by two of my wonderful colleagues, Roy Chan, who’s a member of …
How Old Is The Earth?
I’m in New Zealand’s beautiful Milford Sound, which is actually not a sound but a fjord. So one question you might ask is, what is a fjord? Well, the answer is it’s a giant channel carved out of the rock, and it was carved by glaciers—so ice moving down t…
Social consequences of revolutionary ideals | US history | Khan Academy
During the American Revolution, everyone became a little bit of a philosopher. Walking down the street in Boston, past coffee houses and taverns, you might hear ordinary people debating equality and natural rights. Before it was even a political revolutio…
Identifying key features of exponential functions | Algebra 1 (TX TEKS) | Khan Academy
We’re told to consider the exponential function f where f of x is equal to 3 * 12 to the power of x. Now they ask us several questions about the y-intercept of f, the common ratio of f, and what is the equation of the asymptote of f. So pause this video a…