Not-so-fond memories of our school days might remind us that adjectives describe things. That’s true, but like so much of what we learned about grammar in our early days, more could be said, and that more could make the whole subject of language and composition a lot more interesting.
I had occasion the other day to look up the word replica in the dictionary. Something I was reading was making the distinction between a replica and a copy, and I wondered about the difference between the two. A replica, as the Merriam-Webster dictionary defines it, is a copy exact in all details (a copy, by contrast, is an imitation or representation of an original). I understood the difference, but it was the precise phrasing of the definition of replica that caught my attention: a copy exact in all details, not an exact copy in all details. The dictionary’s careful wording was correct, of course, but how would one explain grammatically why the position of the adjective exact should be after the noun copy and not before it?
An adjective names the quality of something, and a quality is a feature or characteristic or trait that we see something to possess. If I talk about a copy, that’s one thing; if I talk about an exact copy, that’s another: all exact copies are exact, but not all copies are necessarily exact. An adjective can name a quality that defines something essential and inseparable from an object (the blue sky), and it can name a quality that is inessential and separable (a scholar renowned for her teaching). The word adjective in its derivation means thrown at or applied to, and that’s just what we do with an adjective: we throw a quality (blueness) at a noun (sky), and produce a compound substance that names what we see at issue in a certain context. I might want to point to the great blue sky of Wyoming, but then again its color may be less important than how vast and open that Wyoming sky appears just now. A great blue sky is something different from a vast and open sky, and the obligation is on me to name exactly what I’m talking about.
So to speak of an exact copy is to name the quality of exactness and apply that feature to the kind of copy one is thinking about. When an adjective names an essential feature of something, it stands before the noun it is defining, and in that preceding position it is called an attributive adjective (an attribute being an essential feature of something). But when an adjective is qualified in its own right, that is, when something more is said about the adjective itself, then that adjective should follow its noun and the additional information appear immediately afterwards: a copy exact in all details. When an adjective follows its noun like this, it is called a predicate adjective.
And this term predicate adjective makes sense when we realize that a copy exact in all details really means a copy which is exact in all details; the words which is form a predicate, a new clause that is going to assert outright something (exactitude) about the noun copy, and not merely assume it. And one can then comfortably modify the adjective in this newly created predicate: exact in all details. A predicate is the place where things are said and meant, even (ironically) if only implied. If we’re saying something about the adjective exact, then what we’re saying should be right next to that word: exact in all details. So likewise the junk mail that arrives shouldn’t speak of an enclosed envelope for your convenience, but an envelope enclosed for your convenience; and I shouldn’t invite you to a famous restaurant for its desserts, but a restaurant famous for its desserts.
And why? Because adjectives work to specify nouns, and the strength of our language depends in large measure on specificity. Too many adjectives for a noun means we’ve probably chosen the wrong noun (a tall building made of steel and glass is, perhaps, better a skyscraper), but adjectives in the wrong position mean we’ve disarranged the ideas we want to keep. Either way, it’s about being—exact.