Ever since the 16th century there has been a taboo against pointing a knife at our faces. It is rude, of course, to point at anybody with a knife or a fork, or even a spoon; it is also very bad form to hold a knife and fork in the fists so that they stand upright. But pointing a knife at ourselves is viewed with special horror, as Norbert Elias has observed. I think that one reason for this is that we have learned only very recently not to use our knives for placing food in our mouths: we are still learning, and we therefore reinforce our decision by means of a taboo. We think we hate seeing people placing themselves even in the slightest jeopardy, but actually we fervently hope they will not spoil the new rule and let us all down by taking to eating with their knives again.
For the fact is, that people have commonly eaten food impaled on the points of their knives, or carried it to their mouth as balanced on blades; the fork is in this respect merely a variant of the knife. With the coming of forks, knife points became far less useful than they had been; their potential danger soon began in consequence to seem positively barbaric. The first steps in the subduing of the dinner knife were taken in the 17th century, when the two cutting edges of the dagger-like knife were occasionally reduced to one. The blunt side became an upper edge, which is not threatening to the fingers when they are holding knives in the polite manner.
According to Tallement Des Réaux, Richelieu was responsible for the rounding off the points on table knife blades in France in 1669, apparently to prevent their use as toothpicks, but probably also to discourage assassinations at meals. It became illegal for cutlers to make pointed dinner knives or for innkeepers to lay them on their tables. Other countries soon followed suit. Pointed knives for all diners were later to return to the dining room table, but as steak-knives, which have a special image, linked deliberately with red meat and “getting down to business” when hungry. They are still quite rustic in connotation. — Margaret Visser, The Rituals of Dinner
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