THE IMAGE of the hexagram: a large, opened mouth. Upper teeth are in the upper jaw, and lower teeth are in the lower jaw. In between, the open oral cavity, and maybe in the depths you can see the uvula and the dark shaft of the oesophagus? The extended meaning of jaws: feeding, eating.
Below is the thunder, the ultimate moving. Above is the mountain, the archetypal image of non-movement.
A jaw has two halves: one half moves, while the other stays in place. Since Victorian times, we have been expected to move our jaws according to specific etiquette. The upper jaw – and thus the entire skull, to which it is connected – acts as an immobile mountain. Nor do the neck and the rest of the spine give way during the opening and closing of the jaw and mouth. The body is Victorian, straight and rigid. Unmoving. The lips give way only to let in a bite but otherwise stay neatly together. In cultivated eating, the lower jaw stands alone, leaving little in the way of Burgundian ramp pleasure.
A crocodile has nothing to do with named jaw etiquette. Its jaws, in their movement and emotion, are one with its trailing spine and mighty tail. Eating is a matter of the whole body, certainly not an isolated grinding lower jaw. The crocodile's lower jaw depicts the mountain, and his upper jaw and spine the thunder. Try to imitate that movement pattern at today’s supper. Jaw and tail like lightning bolts.
Etiquette equally prohibits all manner of eating noises, as you can see in the spaghetti scene from the Japanese film Tampopo.
A clam does not have a mouth and jaw; it is entirely mouth and jaw. It lacks a torso, arms and legs, but it does have soft lips, a palate, a stomach and gut, and a poop hole. All soft and fragile. The hard calcareous shells are protective armour and jaws at the same time. A jaw that closes decisively and stays closed when approaching predators; one that opens to let tasty morsels float in. An ultimate land of milk and honey?
A double shell and the animal jaw are two different things. They have, to my knowledge, no direct evolutionary connection. Yet the form and function of the hinged clamshell and the jaws of fish, quadrupeds and birds have a handful of similarities.
If an oyster already has a jaw, who will say what the lower jaw and what the upper jaw are? The characteristics of Thunder and Mountain are now reflected in the opening or closing of the two shell halves.
And what is true for eating is equally true for flowing in the opposite direction: speech. Once closed, it takes a long time for the clam to know the coast is safe and open again.
Jaws and teeth manage the boundary between the outer world and the inner. You bite off a piece of a juicy apple with your teeth. A small, tasty piece of that outside world. You chew it, swallow it – and after a few hours, the notion of 'apple' disappears, and it is transformed into your blood. Ultimate loving – the highest degree of identification – opens the jaw, bites, chews, swallows, and out there becomes in here.
But if that outside is dirty, if it stinks, is spoilt and is mouldy, keep your molars together. Don't let the filth come in. For deterrence, show your teeth. Your jaw is like a mediaeval gate with a portcullis – no entrance!!!
The further the jaws spread in a yawn, of all reflexes the least explored and understood. A yawn out of boredom is not an athlete's yawn prior to a competition. What does a gaping wound have in common with a drugstore gaper? What we do know is that yawning is extremely contagious. And not just between conspecifics. Humans yawn; dogs and cats do; our Amazon parrot yawns; hippos and turtles do; and they all stimulate each other to yawn further. It is not known yet whether a yawning oyster makes conspecifics yawn.
