New York Times October 3, 1998 Listening Between the Lines By STEVEN PINKER CAMBRIDGE, Mass. -- W ith the House of Representatives set to decide next week whether to open an impeachment inquiry, President Clinton's fate may ultimately depend on his theories of language. In his grand jury testimony, Mr. Clinton expounded on the semantics of the present tense ("It depends on what the meaning of the word 'is' is") and on the meaning of the words "alone," "cause" and, most notoriously, "sex." Has the President read too much French literary theory? Is he our first postmodernist, poststructuralist, deconstructionist leader, averring that objectivity is impossible, meaning self-contradictory, and reality socially constructed through language? No. Mr. Clinton has long realized that language does have a systematic though complex relation to reality. His semantic arguments, if ultimately unsuccessful, have shown an acute understanding of the logic and psychology of language. Words are anchored to endpoints, but the continuum between them may be up for grabs. A tape measure shows people's heights vary continuously, but when we talk about them, we face a choice between "tall" and "short." People who describe themselves as "middle-aged," "gray" and "wise" cannot pinpoint the instant they became so. The world is analog; language is digital. It would be fun to have Mr. Clinton in a graduate seminar on lexical semantics. He suggested he was not "alone" with Monica Lewinsky because people were in the Oval Office complex at the time. An intriguing point, but since each of us shares the planet with five billion others, none of us are ever unambiguously alone. Exactly how far away, how inaudible or invisible or unnoticed, how thick the barrier, before we are willing to say that someone is "alone"? At what point in the continuum of bodily contact -- from an accidental brush in an elevator to tantric bliss -- do we say that "sex" has occurred? How many times, how closely spaced, before it is "sexual relations" or a "sexual relationship"? When consenting adults come together, does one of them "cause" contact, or are the actions of entities with free will never truly caused? The present tense -- "Mary jogs," "There is a unicorn in the garden" -- is used for states that overlap with the moment of speaking. When an action stretches over time, like standing or sitting, usage is unproblematic. But when an action is more discrete, like swatting a fly or having sex, present tense refers to a span of time in which the event is habitual or repeated. If I say "John is swatting flies," he doesn't have to land a blow at the instant the words come out of my mouth. Mr. Starr's lawyers, when questioning the the President about his deposition, accused him of pedantically restricting "there is sex" to the act of coitus. Mr. Clinton had a point when he replied that the present tense can refer to a span of time over which acts tend to be repeated, and at that point he and Ms. Lewinsky had broken up and were unlikely to have sex again. The termination of a habitual state is inherently vague -- how much time must elapse since the last cigarette before a would-be former smoker can say, "I don't smoke?" Of course, these arguments don't impress anyone but a professor of semantics, thanks to another key feature of language: people work around its limitations by tacitly agreeing on how to use it. Conversation requires cooperation. Listeners assume speakers are conveying information relevant to what they already know and what they want to know. That allows them to hear between the lines in order to pin down the meanings of ambiguous words and fill in the unsaid logical steps. When the shampoo bottle says "Lather, rinse, repeat," we don't spend the rest of our lives in the shower; we infer that it means "repeat once." The expression "to be on speaking terms" reminds us that without cooperation, language is impossible. The reason we cannot converse with our computers is not that the engineers cannot program in the grammar and vocabulary of the English language, but that they cannot program in the common sense of a human speaker. In the old "Get Smart" television series, Maxwell Smart asks the robot Hymie to "give me a hand," and Hymie proceeds to unscrew his hand and hold it out. Mr. Clinton, of course, is not trying to impersonate Hymie. The sketchiness of language gives the listener considerable leeway in pinning an interpretation to an utterance. That is fine when the interlocutors are cooperative -- and the listener's guess is the same as the speaker's intent -- but not when they are adversaries and the interpretation can send someone to jail. he law requires language to do something for which it is badly designed: leave nothing to the imagination. Lawmakers and lawyers do their best to co-opt language for this unnatural job, but even their prolix definitions and legalese inevitably leave room for alternate interpretations that a clever adversary will find. The phrase "the whole truth" is meant to pre-empt such cleverness, but taken literally the whole truth could include one's complete autobiography, the history of the 20th century and so on, so speakers are always entitled to be selective. At some point we have to fall back on the principle of cooperation and judge the truthfulness of a statement by what a cooperative speaker would expect his listeners to infer. Mr. Clinton astutely said, "My goal in this deposition was to be truthful, but not particularly helpful." Unfortunately, when it comes to the truth that listeners want, the very nature of human language makes this goal impossible. Steven Pinker's books include ``The Language Instinct'' and ``How the Mind Works.''