In a previous life as a math nerd, I used to do memory and mental arithmetic tricks, so this post rings true -- i.e, these calculations are all in fact easy to do with practice, even if they might not appear to be so at first.
It appears that the only way to make math cool is by focusing on the least useful part of it, and further, by giving it an aura of mystery by making exaggerated or false claims, when in fact the purpose of math is to clarify. Sad.
Yeah, it's a shame this part of math gets focused on so much. However, that doesn't mean there aren't cool tricks that are handy to know. For instance, to this day I still multiply 2-digit numbers mentally by using difference of squares, just by doing a*b = ((a+b)/2)^2 - ((a-b)/2)^2 (assuming a > b and a+b is even, otherwise cut one of the numbers by 1 and add it back in in the end). This immediately reduces doing two digit multiplication into doing two digit squaring, for which there are some additional techniques (or just brute memorization), so at the minimum you get a 100-fold decrease in required memorization (and likely more). Of course, the above formula is always true, though it gets less usable for higher digits and hopefully most of us can do one digit multiplication in our heads already =)
I thought Art Benjamin's performance was obvious, but he does it under the guise of a "magician," so I would cut him some slack. After all, everybody knows magicians are entertainers. It's hard to be impressed when you can quickly deconstruct the process though.
I was quite impressed by the Tammet documentary, but your analysis is pretty stunning. I actually took everything from the original video at face value, perhaps because I wanted to be amazed by synesthesia.
I won't call it BS just yet -- there could be the possibility that the shape transformations he "sees" are the result of using algorithms in a subconscious manner, the clues of which only manifest themselves like play-doh imagery. It is rather suspicious that after the high-profile reports, there haven't been other publicized and scrutinized reports further documenting his abilities.
In any case, thanks for supplying a kick of realism back into the picture.
In a somewhat related note -- has your training with math tricks given you a "deeper understanding" of numbers per se? Has it facilitated your prowess with abstract and purely symbolic math?
They're different in that they focus on more abstract math - algebra and calculus. In other words, how to solve algebra equations mentally, and how to do calculus operations mentally. Most books I've seen about "mental math" are actually about "mental arithmetic". While I personally see value in it, there is more to math than that.
Actually, I'd love any feedback people may have - both from an educational standpoint, if you have taught algebra and calculus; and from a business standpoint - the two math books are the two products I have now, and I'm thinking about how to better monetize it all, perhaps developing a larger study course kit. Thanks in advance.
(By the way, let me say right away that I'm not claiming to be unusually talented at math, because I'm not... just a typical engineer. Probably most people with an engineering or hard science degree (mine is in physics) will not find much new in the books. I just examined how I and some others solve algebra and calculus problems mentally, and attempted to explain how to replicate it.)
Still, those kind of "tricks" are great to teach schoolchildren, IF it gets them interested in mathematics.
For example, it is actually not that hard (just takes practice/time like everything else) to multiply random 3 or 4 digit numbers: http://en.wikipedia.org/wiki/Trachtenberg_system (great story behind it, as well)
Rapid calculating has about as much to do with real mathematics as double-entry accounting has to the Tao, so I'm at a bit of a loss as to what this fuss is really all about.
Agree. There are some areas where numerical affinity is correlated to actual work being done, say in number theory, but I've seen professional mathematicians stumble over much lesser calculations. Without detracting from the auteur's own talents and achievements, it is of note that he teaches middle school math and is not working on actual research problems.
It appears that the only way to make math cool is by focusing on the least useful part of it, and further, by giving it an aura of mystery by making exaggerated or false claims, when in fact the purpose of math is to clarify. Sad.
In this vein, see also my deconstruction of Arthur Benjamin's "mathemagics" performance: http://arvindn.livejournal.com/82413.html