Comments

  1. Sonja says

    Wow! TimeCube guy has the answer!

    …if the question is “What would the website of a schizophrenic look like?”

  2. says

    They way he built up the tension was pretty good, but it seems spoofy to me.

    This is the kind of the thing that the wingnutosphere are good at debunking. Send it to LGF and Buttrocket. It will keep them out of trouble for awhile.

  3. Steve_C says

    I think he did it. That was awesome. He essentially made his arm a compass and just rotated his arm really well.

  4. Ruth says

    When I was at Michigan Tech (Houghton) in the late 70’s, a physics professor did this regularly as part of the lecture, no fuss or build-up.

  5. says

    I’ve seen a number of engineers and architects who can draw perfect circles and straight lines freehand. It mostly requires practice.

    I’m an expert at freehand drawing of mangled sort-of-quasi-ellipsoid-roundish-shapes-that-have-to-pass-for-circles

  6. Morgan says

    Pah! I’m peeved they didn’t attempt any sort of verification or measurement. What would really have been interesting would be seeing how close to a circle it actually was, using something more precise than eyeballing.

  7. Theo Bromine says

    I recall seeing a prof at MIT doing this in the late 70s, as well as some students trying to emulate him. While it is impressive to see, it seems to me similar to feats of very accurate throwing, catching, hitting etc, not to mention leaping and spinning (that are unattainable for me personally, but evidently possible for some humans).

    (I wonder how much more difficult it is to do with a whiteboard marker.)

  8. C.W. says

    Once I saw a professor do the same trick with two hands. He first drew a half-circle with his right hand. Then, without slowing down, he took over the chalk with his left hand and completed the perfect-looking circle.

  9. Becca says

    Kids in Waldorf schools are regularly taught how to do this. I can’t do it, but apparently once you know the trick it’s no big deal.

  10. cnmyers says

    My high school math teacher was really good at this too. He used his forearm as the radius instead of his whole arm though, so he had to smudge the bottom of the circle a bit since a whole circle would entail some bones breaking…

  11. AnthonyK says

    Giotto (1267-1337)
    Vasari tells the story of how Pope Boniface VIII sent a messenger to Giotto with a request for samples of his work. Giotto dipped his brush in red and with one continuous stroke painted a perfect circle. He then assured the messenger that the worth of this sample would be recognized. When the pope saw it, he “instantly perceived that Giotto surpassed all other painters of his time.”

    Do you suppose that this teacher has the talents of Giotto?

  12. James says

    My highschool math teacher, Mr. Wood, could do it as well. He’d plant his elbow in the middle of the blackboard to start, and the last little bit usually went off on a tangent, but it was pretty close.

  13. Richard says

    Good ol’ Mr. Norton, my high school Physics teacher, was able to do the same thing. He was held in awe by his students and in addition to being a master circle-maker, he was a terrific teacher.

  14. fusilier says

    OK, will you guys tell me what ->really<- is at the link? I got "Websense" blocked. Let's just say, (tm from another list) it took me two bleeping years to get our IT Nazis to unblock links to my own papers on diagnosis of breast cancer. fusilier James 2:24

  15. fusilier says

    Bleah – sorry for not previewing. Minor unfunny joke about getting blocked at work by “Websense.”

    fusilier
    James 2:24

  16. says

    My dad had a math prof that could do this as well – he would start off the lecture by drawing a huge circle on the board, and then use it to illustrate whatever he was teaching that day. Since it all worked out, the circle must have been close enough to perfect.

  17. wjv says

    All the perfect-circle-drawers I’ve ever seen have roughly the same technique: They stand side-on to the blackboard, or sometimes even face obliquely away from it, drawing behind their backs without looking at the board.

    Just thought I’d offer this as a data point; I’ve not studied the phenomenon.

  18. says

    I too would have liked a verification. It could have been crappy resolution, but the bottom of the circle looked like it stuck out a little.

    Timecube! This guy’s hilarious! It would of course be Time Square… because a cube is one of those evil objects that follow stoopid Euclidean Geometry!

  19. says

    For those of you not in the know, “squaring the circle” is one of the big 3 classic problems of ancient Greece. That is, mathematicians from way back made attempts at creating a square with the same area as a cirle. However, it has been shown that using straight edge and compass, it is impossible. That Pi is sure hard length to construct.

    Also for you curious types, the other two problems are tri-secting an arbitrary angle, and doubling a cubes volume. (All three are impossible…)

  20. lytefoot says

    Let the floodgates of the angle trisection theories be opened, now that someone’s mentioned it, heh…

    It’s bloody hard drawing a circle on the board. Once you know the trick (which, as many have surmised, involves using your shoulder or elbow as a pivot), you need to convince your arm to relax enough to pivot about that point. This *is* a skill the circle-drawer has in common with a good artist.

    It’s only very slightly harder on a white board, because of the shape of the marker tip. It scales pretty well, but there’s a minimum convenient size; but small ones are pretty easy to fake.

    Oh, and yes, the bottom looks a little funny. They usually do, for anatomical reasons. This guy’s pretty good at minimizing that, though, and I’m impressed by his ability to make his line meet itself so precisely.

  21. says

    I went to a Waldorf high school and yes we did draw many circles (as well as sit in quit a few), but never practiced such an arbitrary talent. Still I have little doubt that a few of my teachers did work on it, but I have never seen it done that well (my high school teachers would have envy)! Yet, of course, it is not perfect- but it is a seeming VERY symmetrical circle and I can think of no reason to believe that it can’t be done with a bit of practice like many other talents. But come on, what is our criterion for “perfect”? This is impressive non-the-less!

  22. coracle says

    Woah, did anyone else have something try to install when they clicked the link? I think it called itself scansafe but I didn’t hang about to double check that.