In PI 133, Wittgenstein talks of “complete clarity”. It is a clarity in which the philosophical problems completely disappear. Wittgenstein’s notion of clarity is connected with the notion of silence. Let me now say something brief about that. To do so, I distinguish between transitive and intransitive silence.
Think of transitive silence as a silence that involves the silencing of something or other, of something that has more to say but is cut off, shut up. (“Her unexpected laughter silenced his protestation of love.”) Transitive silence gags the problems. Intransitive silence is simple silence, a quiet in which nothing is forceably quieted, an untaut stillness. Peace. Genuine peace, not a detente with the problems, in which they hold their peace.
Wittgenstein does not aim at transitive silence; he aims at intransitive silence. He aims at a silence in which the philosophical problems have been played out, utterly exhausted, at a silence unbroken by problems. The problems have had their say, said their piece; they do not even murmur. Noiselessly, they dissipate. They go to their rest. To be completely clear in philosophy, to have made the problems disappear, is to have achieved intransitive silence.
How can intransitive silence be achieved? PI is the answer to that. But let me isolate one central theme: We can only achieve it by deeply sympathizing with the philosophical problems. We must, as it were, become the problems; we must hear the words of the problem as if each of the words comes urgently from the depths of our own consciousness. And whatever words we speak to the problem must themselves come from us just as urgently and from just the same depth. The problems take possession of us and then we must exorcise them. So we can only cause the problems to disappear on pain of risking that the problems will take lifelong possession of us, that they will resist exorcism, that our heads will spin permanently.

