THE MORE WORDS YOU know, the higher you climb the evolutionary ladder. Don’t take my word for it. Ask God – or Darwin.

Professor Erich Jarvis has studied the “vocabulary” of songbirds and concluded that the more complicated the syntax of the song, the more “words” and phrases it contains, the more attractive that bird seems to the opposite sex.

Words, in other words, are sexy. Increase your word power and you increase your chances of mating with other members of your species similarly evolved, and thus have offspring with even larger vocabularies who will thrash you at Scrabble.

Words are power, and pleasure. They are the individual cells that make up the body of language, the capacity for complex communication that sets us apart from other animals (our nearest rival being Kanzi, a male bonobo ape at Georgia State University, who is said to have mastered 3,000 words; the OED contains 300,000).

Words make us human: knowing more words makes us more human.

Bishops, broadcasters, grammarians, prescriptive punctuationists and the like tend to bemoan the decline of language, but the word bank has never been fuller or richer. According to Paul Payack, who runs the online Global Language Monitor, there are at present 994,638 words in English with hundreds more emerging daily. For every French word, there are ten in English.

Many are slang, abbreviations, thefts from other languages, hybrids or acronyms that would not find favour with the OED, but they are still words, in a vocabulary that is constantly evolving, adapting and expanding. So far from entering a tongue-tied digital age, the internet and mobile telephony have lent words even greater primacy: by e-mail and text message, through keyboard and telephone, we are exchanging words faster than ever.

Quality of words is more important than quantity. Jane Austen used 6,798 different words in her books, rather fewer than the 7,500 considered necessary today to write and speak fluently. James Joyce deployed 19,903.

There is no human activity (except sleep) that would not be improved by the addition, not of more words, but of better ones. Whether one is a novelist, politician or kidnapper, finding the right words for the novel, the speech, and the ransom note is essential. Even traffic wardens need a healthy store, to parry the others thrown at them.

Words can be deceptive. The apparently gentle word “purr”, in Scottish Gaelic, means “to headbutt”. Words can be hijacked and misused. Powerful men, for good or ill (both Hitler and Churchill), have understand the might of words. In 1940, a 12-year-old boy wrote to President Roosevelt, asking for help expanding his English vocabulary: “I don’t know English but I know very much Spanish and I suppose you don’t know very Spanish but you know very English because you are American.” The boy’s name was Fidel Castro.

Words extend the horizon, and our knowledge of ourselves. When Hamlet in Act II, scene 2, is asked what he is reading, he replies “Words, words, words”. He may seem dismissive, but words are part of Hamlet’s quest: through words, he is seeking the answer to the question of to be, or not.

Word power is not about using a complicated and obscure word where a short or familiar one is already at hand. It is not about waving your vocab around to attract a mate. It is about the discovery of a word to describe something in a new and unexpected way.

Adopt a new word. Take it home. Add it to your word family and introduce it to the others in your collection. They will play with each other, form new patterns and meanings, making the world a little bigger, a little clearer.

Tom Stoppard observed: “Words are innocent, neutral, precise, standing for this, defining that, meaning the other, so if you look after them you can build bridges across incomprehension and chaos . . . They deserve respect. If you get the right ones in the right order, you can nudge the world a little or make a poem which children will speak for you when you are dead.”

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