不可說的，只可不說 Whereof One Cannot Speak, Thereof One Must Be Silent

維特根斯坦說：「不可說的，只可不說。」	"Whereof one cannot speak, thereof one must be silent," said Wittgenstein.
在這裡，知道不可說的某物卻不知道它不可說的，或甚至不知道不可說的，或根本不知道某物的，都算是違反這個要領。可見遵守這個要領是很難得的。	Herein, a person violates the rule if he does not know one of the inexpressiblility of a known inexpressible thing, or even the concept of inexpressiblility, or more even the existence of a thing. We thus see it is difficult to follow the rule.