In the interest of seeing more precisely how language works from the inside out, let’s look at this sentence I happened to read the other day: But for reason, we humans are merely animals. We generally think of tone as a notion applying to the entirety of a piece of writing—essay, novel, poem, but an entire composition is composed of component sentences, each, through its choice of words and resulting phrases, impressing its ideas on the reader by a certain affect it evokes. To write but for reason instead of except for or without reason, is to decide for and reveal one’s own attitude to the subject. And to understand the grammatical structure of that attitude is, still more, to appreciate all the more deeply the ideas and thoughts the writer wishes to convey.
Tone is feeling, and if there is a meaningful distinction to be made between feeling and emotion, feeling is elemental, emotion circumstantial (or more philosophically, feeling has to do with the self, emotion with the ego). Tone, as Thomas Kane remarks in his excellent New Oxford Guide to Writing, “is a web of feelings stretched throughout an essay,” and it has, he says, “three main strands: the writer’s attitude toward subject, reader, and self.” I as a reader, in other words, can learn by listening to the tone of a passage, whose meaning and fundamental feeling dwell in a particular grammatical structure.
At first glance we easily see that the sentence but for reason, we humans are merely animals has only one clause, the independent assertion that we humans | are merely animals (the subject is properly the pronoun we, with the noun humans standing as a restrictive appositive to it). The sentence opens, however, with a phrase whose condensed meaning indispensably qualifies the meaning of that one assertion, doing so not by explicit assertion, but by implication. The two words but for comprise what is called a phrasal preposition. We usually think of a preposition as one single word (to, with, in, for example), but a phrasal preposition recognizes two or three words acting together as a single preposition (because of, in front of, on account of, being other examples). The object of but for, then, is the noun reason, and with that short initial phrase, an exception is being alluded to which will limit the logical extent of the immediately following independent clause, we humans are merely animals.
This particular phrasal preposition usually holds an elevated position in English diction, and so we owe it to ourselves as close readers to ask what difference this more elaborate expression makes here, when other prepositions, the phrasal except for or the simple without, were just as available. The answer lies in the profundity of the idea, as the writer sees it, which the sentence states. Phrases imply and clauses assert, and so to choose to open the sentence with a phrase in order to say that the absence of something involves us in an abstrusity when we’re talking about the very nature of a human being, means that the writer likely wants to underscore this depth with an unusual phrasal preposition of higher, almost literary diction. Uncommon form to match exceptional meaning.
To illustrate the difference diction can make, we might compare two versions of a sentence that has to do with a much more ordinary concern: Except for the automatic transmission, I really like this truck, and But for the automatic transmission, I really like this truck. Would anyone really say or write the second version? (To appeal to the ear is proper here, let us note, because our question is strictly a matter of rhetoric, not grammar.) Most of us would not, because of what is called the universe of discourse, the entire subject matter we’re talking about. The topic is everyday, and so our diction should mirror that. We have to always be clear minded about how the words we analyze are being used at the moment (but, for example, has the potential to serve as five different parts of speech); with that caution and a sense of context, however, the better we examine form, the more certain we can be of the interpretation we make of a sentence.
This procedure of asking why this word or phrase and not another, why this and not that grammatical construction, gets for us, in the end, an incisive look at what may lie behind the objective words we read, when we could otherwise be too quickly sure of their meaning and miss all that the writer might be implying. And it’s there, behind the obvious, that meaning and its tone, its feeling, have their source—of both their expression and our pleasure of understanding.
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