If I happen to say that the planet Neptune has sixteen moons, I am making a specific, or finite, qualification to the noun moons. If I go on to say that I believe the universe is infinite, I mean to say that there is no specific measure which can be taken of its extent. The stem of both these adjectives, fin, derives from the Latin noun finis, meaning border or end or limit. We limit something by putting a border around it, and thus we define it; and if we cannot define something, literally or conceptually, we say that it is indefinite.
The terms finite and infinite have found their way into traditional grammar, and knowing what they refer to can help us design our sentences in more interesting ways. When we are revising and ask what the verb of the sentence is, we’re really asking what the finite verb of the clause is. We say, for example, that the sentence I opened the kitchen window has one clause because the subject I is paired with the predicate opened the kitchen window, and if we wish to be quite precise in our analysis, we’ll say that the finite verb of the predicate is opened—finite because a subject (I) and a tense (simple past) can be specifically identified for it. Every finite verb form has its corresponding infinitive form, which merely names the action, unassociated for a moment with any subject or tense. The infinitive is the form which appears listed as the headword in a dictionary; for the finite form opened, the infinitive would be to open.
A finite verb form, then, constitutes the gearwork of a clause, whether independent or subordinate, putting the assertion into motion. Note closely right here, though, that in the sentence I just wrote, the finite verb is constitutes and the phrase a finite verb form is its subject. But what, then, is putting? We certainly perceive some sense of action in the closing phrase putting the assertion into motion, but neither a subject nor a tense is readily apparent for the word putting. The answer lies in an entirely distinct category of verb forms called nonfinite or infinite, of which there are three: the infinitive, the gerund, and the participle. The nomenclature of nonfinite or infinite immediately tells us that these forms are unspecific, and that means that they are not working to produce a clause, as do finite verbs. Instead, they make up phrases, and that changes their operative value from assertion to modification. An infinitive (to open), as we saw above, simply names the verbal idea, and that is the function of a gerund (opening) as well. Both of these nonfinite verb forms, therefore, can be called verbal nouns because they are built from verbal material.
The form putting, however, is called a participle, more exactly, a present participle. It too ends, like the gerund, in the suffix –ing, but unlike the gerund, which is a verbal noun, the participle is a verbal adjective. It can be said to modify (but not assert) a subject, and it can be said to refer to relative, not actual, time. Under those defining restrictions, then, we cannot say that the phrase putting the assertion into motion is making a finite assertion; to do that would require that we attach a subject and refer to an actual phase of time as, for example, in it puts the assertion into motion. With that change, we have revised a participial phrase into a clause, and have transformed the original simple sentence into a compound one: A finite verb form, then, constitutes the gearwork of a clause, whether independent or subordinate; it puts the assertion into motion. (Note that there is now a semicolon in this revision to take the place of the understood conjunction and between the two clauses. Placing a comma there instead of a semicolon would have created a run-on sentence.)
Knowing a little about these infinite verb forms can open a whole new world of more precise and subtle language. We can replace an infinitive with a gerund: to walk to work takes too much time, becomes walking to work takes too much time. We can replace a subordinate clause with a participial phrase: because I cooked the rice in advance, I was able to prepare my dinner quickly, becomes cooking the rice in advance, I was able to prepare my dinner quickly. Or we can use the present participle to build the progressive aspect of a verb: he arrives this afternoon is made more vivid with he is arriving this afternoon. Each of these changes refines the perceptive quality of the statement: precision lies at the heart of style.
Infinite constructions, particularly with the participle, give us a way to suggest an assertion without explicitly stating it, as a clause would accomplish. This brings color and nuance to an otherwise black and white perceptual world, helping us write more nearly in accord with the world as we know it—complex but variegated, present but suggestive of so much more.
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