The critic, Yvor Winters [1900-1968] published a long essay on Gerard Manley Hopkins in the first two issues of the Hudson Review in 1949.¹ In the second section of his essay, Winters mocked McLuhan’s 1944 essay on Hopkins’ Windhover:

M.H. McLuhan, in an essay in which interpretation is often carried so far from the actual text as to approach pure fantasy…

This prompted McLuhan to draft a letter to the Editor of The Hudson Review, which he left in an issue of the review now to be found among his books at Fisher Library in Toronto:² 

Sir, It has long been the practice of Mr. Winters to paddle his critical canoe into white waters and there to complain that, by his powers, this was no mill pond. So long, however, as he stays with the literature of simple statement and naive sentiment, his method will bear him up even when it can’t possibly carry him forward.³
Instead, therefore, of rescuing him from the dramatic and turbulent mill-race of Hopkins (he had the same harrowing experience with Joyce and Eliot), it will be more useful to explain why Mr. Winters should above all avoid poets who have a radically analogical outlook.
Analogies are not concepts, nor are they reducible to concepts. They are proportions between congeries of various forms, facts, concepts. Such proportions are for contemplation. They are inexhaustible and irreducible. When Wordsworth presents Lucy in the ratio of “a violet by a mossy stone”, he renders his world. Every conflict, pathos, paradox of his entire vision is there. A violet needs the stone, it needs the moss, and the converse is both true and untrue at different levels.
In short, even this simple statement is not the poetry of concepts or of statements.  Poetry is never merely or primarily an affair of essences and concepts. It is in the order of existence and experience. Yet Mr. Winters asserts that poetry is statement about experience. And poetic order must be, he holds, logical coherence of concepts or judgements about experience. This notion of poetry is not as uncommon today as Mr. Winters claims. If anything it is the conventional nineteenth century view inherited from Cartesian and Kantian notions of language as merely conceptual signs. And it is a view which compels the critic to view with distaste all the complex art of our or any other time. Let us recall Rhymer⁴ and les règles⁵.
Even Pope is not as much the poet of simple statement as was once supposed. Wherever there is serious poetry, analogy will be present. Wherever there is analogy, Mr. Winters will prove helpless as a critic. And yet it was the discovery of that very eighteenth century, to which Mr. Winters so often appeals for his criteria, that all four terms of an analogy could be managed in a single couplet. That is, a couplet could contain a compressed drama containing both plot and subplot, comprising within itself metaphors as well. Yet every metaphor is itself an analogy in four terms, only two of which need be expressed.

The hungry judges soon the sentence sign
And wretches hang that jurymen may dine.

“As hungry judges are to justice, so are the victims of justice to the appetites of their fellow men.” Within this ratio is included the same tragic vision as that of Lear on the heath and of Swift’s Modest Proposal [1729]. It is a vision of treachery and cannibalism occurring independently at various social levels and it cannot be reduced to a logical order of concepts and retain the dramatic conflict. It is true that judges are hungry, but not for justice. And it is true that wretches are fed into the social machine to feed other wretches. Meat must be hung before it is eaten.⁶ But from these observations neither Shakespeare, Pope nor Swift concluded anything logically. (The merely conceptual mind would say that, if only the judge could have a sandwich brought in, then justice would supplant injustice.) They set their observations in a ratio, proportion or analogy which is for contemplation and not to be reduced to a univocal order of conceptual awareness or causal connection.
It is not only Mr. Winters, therefore, who finds himself in difficulties in the presence of analogical awareness. It is still the typical intellectual difficulty of our world as can be seen, for example, in the current efforts to reduce Eliot’s notes on the analogy of culture to a univocal conceptual scheme.

The summer 1949 issue (2:2) of The Hudson Review featured two reviews of ‘Mr. Eliot’s New Book‘, Notes Towards the Definition of Culture, by Herbert Read and by Hugh Kenner. It may be that the last sentence of McLuhan’s draft refers to these reviews, or at least to Read’s, and thereby gives an indication of the “current” date of the draft’s composition.