One of my friends says that his Kung Fu teacher said that trying to break boards in the wrong way can cause nerve damage in the hands, and that this nerve damage can cause blindness of the eyes, through some kind of neural connection between them, or something.
So I suppose that breaking boards in the ‘wrong way’ can damage your hands. But why this should do anything to your sight is beyond me. It’s probably just a tale they tell to stop them trying it at home.
Use this method to impress your friends and amaze your enemies:
Purchase a 6 foot 1 x 12 pine board.
Cut said board to 6 inch lengths.
Chop away! It’s easy!
Why is it easy? the grain of the small boards you created is perpindicular to the length of the board. Breaking a board of continious grain is very difficult. Breaking a board that has had all the grain cut is easy. The strength of wood lies in the grain.
The boards are easy to break because the wood has been cut into lengths against, rather than with, the grain. This means grain runs across the board and not along it. No additional cutting or scoring required.
I don’t know if this wood would still be tough enough to hurt your hand. I suppose you’d have to be careful of where the knots were. But it is still very much easier to break than the lengths of wood you’d normally encounter. No timber-merchant would choose to cut wood in this way, as the resulting boards are totally useless for any kind of construction.
So, to get back to the OP, the instructor was spinning a line to stop his pupils going home and trying it out. Any wood they might have lying around at home is practically guaranteed to have been cut the correct way and be nearly impossible to chop with your hand. The fact he didn’t just own up to this, making up some nonsense instead, gives credence to Randi’s opinion that the whole ‘chopping wood’ thing is a bit of a cheap party trick.
This doesn’t mean that everything else these guys can do is a fraud or that the martial art in question has no merit. I wouldn’t want anyone deciding to come around and give me a practical demonstration!
The optic nerve is a cranial nerve–direct link to the brain, doesn’t go through the spinal column. (I’m pretty sure that’s also true of every nerve having anything to do with the operation of the eyes/eyelids/etc.) The notion that a hand injury can affect one’s sight strikes me as patently ridiculous.
Hm. The thing is wood grains are concentric circles (more or less) . Unless you are talking about really, really big trees there really isn’t a whole lot of choice how wood blocks are sliced. In other words, there isn’t much against or with the grain per se.
Anyway, even if I cede the point of them using trickery with wooden planks, what about bricks?
Have a look at a piece of wood sometime. Wood is cut for strength as described above, with the grain running the length of the board. The way grain runs is everything in wood. It gives it strength, it gives it tone and flexibility when used on musical instruments.
Yes, many claims of breaking multiple blocks of ice with seemingly superhuman strength and such is quite far fetched to say the least. Same goes for the wooden boards – they ARE easier to break because of the grain–however, it isn’t easy to break multiple boards…say 4~5. I’ve seen people break red bricks too, totally insane considering I couldnt even get one to split down the middle with a hammer.