Word has somehow got around that a split infinitive is always wrong. This is of a piece with the sentimental and outworn notion that it is always wrong to strike a lady. Everybody will recall at least one woman of his acquaintance whom, at one time, or another, he has had to punch or slap. I have in mind a charming lady who is overcome by the unaccountable desire, at formal dinners with red and white wines, to climb up on the table and lie down. Her dinner companions used at first to pinch her, under cover of the conversation, but she pinched right back or, what is even less, defensible, tickled. They finally learned that they could make her hold her seat only by fetching her a smart downward blow on the head. She would then sit quietly through the rest of the dinner, smiling dreamily and nodding at people, and looking altogether charming.
A man who does not know his own strength could, of course, all too easily overshoot the mark and, instead of producing the delightful languor to which I have alluded, knock his companion completely under the table, an awkward situation which should be avoided at all costs because it would leave two men seated next to each other. I know of one man who, to avert this faux pas, used to punch his dinner companion in the side (she would begin to cry during the red-wine courses), a blow which can be executed, as a rule, with less fuss, but which has the disadvantage of almost always causing the person who is struck to shout. The hostess, in order to put her guest at her ease, must shout too, which is almost certain to arouse one of those nervous, high-strung men, so common at formal dinners, to such a pitch that he will begin throwing things. There is nothing more deplorable than the spectacle of a formal dinner party ending in a brawl. And yet it is surprising how even the most cultured and charming people can go utterly to pieces when something is unexpectedly thrown at table. They instantly have an overwhleming desire to "join in." Everybody has, at one time or another, experienced the urge to throw a plate of jelly or a half grapefruit, an urge comparable to the inclination that suddenly assails one to leap from high places. Usually this tendency passes as quickly as it comes, but it is astounding how rapidly it can be converted into action once the spell of dignity and well-bred reserve is broken by the sight of, say, a green-glass salad plate flying through the air. It is all but impossible to sit quietly by while someone is throwing salad plates. one is stirred to participation not only by the swift progress of the objects and their crash as they hit something, but also by the cries of "Whammy!" and "Whoop!", with which most men accompany the act of hurling plates. In the end someone is bound to be caught over the eye by a badly aimed plate and rendered unconscious.
My contemporary, Mr Fowler, in a painstaking analysis of the split infinitive, divides the English-speaking world into five classes as regards this construction: those who don't know and don't care, those who don't know and do care, those who know and approve, those who know and condemn, and those who know and discriminate. (The fact that there was no transition at all between the preceding paragraph and this one does not mean that I did not try, in several different ways, to get back to the split infinitive logically. As in a bridge hand, the absence of a reentry is not always the fault of the man who is playing the hand, but of the way the cards lie in the dummy. To say more would only make it more difficult that it now is, if possible, to get back to Mr. Fowler.) Mr Fowler's point is, of course, that there are good split infinitives and bad ones. For instance, he contends that it is better to say "Our object is to further cement trade relations," thus splitting "to cement," than to say "Our object is further to cement trade relations," because the use of "further" before "to cement" might lead the reader to think it had the weight of "moreover" rather than of "increasingly." My own way out of all this confusion would be simply to say "Our object is to let trade relations ride," that is, give them up, let them go. Some people would regard the abandonment of trade relations, merely for the purpose of avoiding grammatical confusion, as a weak-kneed and unpatriotic action. That, it seems to me, is a matter for each person to decide for himself. A man who, like myself, has no knowledge at all of trade relations, cannot be expected to take the same interest in cementing them as, say, the statesman or the politician. This is no reflection on trade relations.
James Thurber:
Ladies' and Gentlemen's Guide to Modern English Usage