As a woodblock printmaker working in an old-fashioned delicate style of carving, I have to be quite careful with my eyes. I keep the workbench well lighted, and avoid eye-strain as much as possible, taking a break anytime that my eyes feel tired.
But do you know that my ears too, are very important to my work? Perhaps they are just as important as my eyes! All the time that I sit there on my zabuton, carving away, my ears are filled with the sound of ... my knifeblade slicing its way through the hard cherry wood. Have you ever heard such a sound? One has to listen very carefully to catch it!
By listening carefully to this delicate sound, I can tell if my knife has been sharpened well or not. If I have done a good job with my shiageto, the sound is barely audible, just a faint trace as the knife passes along the lines of the hanshita. But if I have been careless during the sharpening, the knife then tears the wood a little bit, and my ears tell me at once that something is wrong. I cannot see the difference between a well-sharpened knife and a poorly-sharpened one. But my ears can tell the difference.
So I have to be careful, not only of my eye-sight, but of my hearing as well. I guess it's a good thing that my days of playing in a rock and roll band back in my twenties didn't last very long!