A few miscellaneous comments, in the
tradition of the Chinese
biji or random note.
Most of Jinmyo's comments on chopstick etiquette, drawn from Japanese custom, apply in Taiwan, as well. Taiwan native (pre-1949) popular culture, while fundamentally Chinese, is heavily influenced by Japan. But many of these matters discussed by Jinmyo are widespread East Asian practices.
Not all, however.
We are told in Taiwan that the reason not to stick chopsticks unpright in a bowl of food (specifically, cooked rice) is that this is how food is offered to the dead. But I was surprised when living in Longyan (in western Fujian Province), an area of Mainland China with close historical links to Taiwan, to find that people did often stick their chopsticks upright in their food, even their rice, before eating it. This seemed to be a way of indicating that that particular bowl of rice was spoken for. The old men of the areas I was living in told me there was no taboo on this. The taboo was on placing the tips of the chopsticks on the edge of one's ricebowl, with the ends on the table. That is the taboo act, because that is how food is offered to the dead in Longyan.
In Taiwan there is no particular taboo on passing items from one pair of chopsticks to another, because (to my knowledge) this is not a funeral ritual. But it would be a strange thing to do, nonetheless - the tip of the chopstick often touches the mouth, and people would feel it was unclean to touch chopstick tips. (At formal meals, however, it is not uncommon for the host to take some food from his or her own plate and place it on the plate of the guest of honor, using the same chopsticks he or she eats with. This is not necessarily done before the host has begun eating.)
Chinese culture, both Mainland and Taiwanese, favors holding the rice bowl in one's cupped left hand, close to the mouth, and eating from it with the chopsticks. If you take a bit of food from a serving dish, you may place it briefly in the bowl, which thus serves as a kind of bib, catching dropped food and juice. As I understand it, Japanese people insist that the rice be kept clean of food and drippings. And I am told that in Korea it is considered undignified to lift the bowl from the table, while in China I have been told that "we pick up our bowls so as to be different from the animals", which eat with lowered heads.
I believe the English word "chopstick" is a kind of calque of the Mandarin word kuaizi (kuaytz), which is recorded to be a late "taboo avoidance" term. The classical word for chopstick is zhu4 (juh), which is still used in many southern Chinese dialects. But in the north, it sounds the same as “to stop” or "to get stuck", and so became considered unlucky by boatmen. In order to avoid this inauspicious sound, the custom came about of calling chopsticks “fast-moving thing”, or kuaizi. I believe our English word “chopstick” reflects the meaning “fast”, based on the Pidgin English word “chop-chop”, meaning “fast”.