There is room for some thought of necessity in §241—

'"So you are saying that human agreement decides what is true and what is false?" – What is true or false is what human beings say; and it is in their language that human beings agree. This is agreement not in opinions, but rather in form of life.'

—but it is thought of as more fragile, more contingent, than some philosophers hitherto had thought of it. Something which is the condition of our saying things that are true or false, something embodied in the language we share and expressed in how we live our lives, but also something whose importance we cannot express much more emphatically than to say that we do things the same way, we share the same language, we agree—always at risk of being doubted as to what counts as 'the same' or how much is enough to count, always exposed to questions about who exactly 'we' is.

The context of a later remark about grammar in the Investigations—'Essence is expressed by grammar' (§371)—includes a passage in which Wittgenstein talks of essences just when he seeks to substitute one question for another:

'370. One ought to ask, not what images are or what goes on when one imagines something, but how the word "imagination" is used. But that does not mean that I want to talk only about words. For the question of what imagination essentially is, is as much about the word "imagination" as my question. And I am only saying that this question is not to be clarified – neither for the person who does the imagining, nor for anyone else – by pointing; nor yet by a description of some process. The first question also asks for the clarification of a word; but it makes us expect a wrong kind of answer.'

Compare to §92, from the stretch of remarks on logic and philosophy, which also draws a contrast between questions:

'92. This finds expression in the question of the essence of language, of propositions, of thought. – For although we, in our investigations, are trying to understand the nature of language – its function, its structure – yet this is not what that question has in view. For it sees the essence of things not as something that already lies open to view, and that becomes surveyable through a process of ordering, but as something that lies beneath the surface. Something that lies within, which we perceive when we see right into the thing, and which an analysis is supposed to unearth.

'The essence is hidden from us': this is the form our problem now assumes. We ask: "What is language?", "What is a proposition?" And the answer to these questions is to be given once for all, and independently of any future experience.'

The oracle's response to Diogenes of Sinope: 'paracharattein to nomisma'—deface the coinage.

'… withdrew in disgust to the mountains…'

'… to refine, to clarify, to intensify…'

But then, skies, uncharacteristically blue.

... other rainy days in other cities.

'Acknowledgement of the other in their specific relation to me' is acknowledgement of the history between us, of the aspects of them, and their past, and their relations to others, which they have revealed to me, as well as in some way acknowledgement of what of them is left out, or implied, or yet to be revealed, in the course of life with them or at their discretion; to acknowledge the other’s specific relation to me is at least in a sidelong way an acknowledgement of the particular shape of the unrevealed and unrealized part of their life as it stands behind that part of their life to which I have been privy.

One attenuated, or focused, form of this acknowledgement is to acknowledge the other’s independence from me, to acknowledge that they are not there for me alone or there in only the respects of concern or interest to me. For this is simply an acknowledgement of the potential gap between their life as lived within the most immediate scope of mine, and their life in its full scope, in the course it may take or the actions in which it may issue, at any given absence from me.

Wallace's review of Markson's Wittgenstein's Mistress is in many ways a woeful combination of good intentions, useful observations, interpretative blunders, and scholarly malpractice, of the sort that makes me nevertheless want to run home and look for my copy of Markson. But I wonder if the essential phrase, signalling a deep difference between Wallace's own interest in ordinary life and the interests of people like Cavell in 'the ordinary' or (as Cavell groups them) Wittgenstein's in 'ordinary language' or Emerson and Thoreau's in 'the common, the familiar, the near, the low', might not be the little one Wallace uses to describe ordinary language when he's giving his Investigations crib, referring to that work's 'new & clinical focus on the near-Nixonian trickiness of ordinary language itself'. Nixonian! Clearly we are not all quite on the same page here. Or at least not starting on the same one.