Somewhere around 6,000 years ago, illiterate people somewhere in Eurasia began to spread out from their homeland. Eventually, around 3,000 years ago, some of them entered Scandinavia, where their speech developed into Proto-Germanic. The speakers of this language then spread southward into much of northern Europe, where their language began breaking up into a number of distinct regional varieties. One group moved into the North Sea coast of the Continent, where their speech developed into a collection of local varieties we call Ingvaeonic. After the Roman retreat from Britain, some of these Ingvaeonic speakers moved into Britain, where their speech gradually diverged from that of their relatives back home, until finally it was so different that it had to be regarded as a different language. And that language is the ancestor of our own English.

And this brings us to a famous issue in linguistics, known as the Saussurean paradox. How can we continue to speak a language effectively while it is constantly changing? After all, how could we play chess or football if the rules were constantly changing during a match? Long ago, English had a complete set of distinctive verb-forms for talking about hypothetical states of affairs, the subjunctive. Most of these forms disappeared long ago, but a few cling to the edges of the language, including the one shown in if it were. You may or may not use this form, but you probably at least recognize it. It continues to exist in the language, even though most people now say if the law was constantly changing. Some people say were all the time in this construction; some say was all the time but understand were; and some people vary, using were in some circumstances but was in others.

The key here is variation. Both forms, were and was, exist side by side in English, and both are used and understood. Once upon a time, everybody said were. And one day in the future, everybody will say was. Meanwhile, we have variation. And variation, we now understand, is the vehicle of change. When a change is in progress, the older form and the newer form coexist, and almost everybody is familiar with both forms, even if some people use only one or the other. Over time, the older form becomes less and less frequent, and the newer one becomes ever more frequent, until, one day, there is no one left alive still using the older form, and the change is complete. So, for example, before the Norman Conquest of England, all English-speakers said “here” for “army”. Some time after the Conquest, a few people began to use the Norman French word army when speaking English. For a long time, the two words coexisted in English. But more and more people began to use army in preference to here, and finally a day came when there was no one left saying here at all, and the word became extinct. Today this old word survives only in a few place-names, such as Hereford in England (“army-ford”), and no one except a specialist any longer knows what this name means.

We can choose between telephone and phone, between gymnasium and gym, between omnibus and bus, between brassière and bra, and after a while one form is no longer used at all – as has now happened with omnibus, and perhaps also with brassière. The study of variation in language is sociolinguistics, and the sociolinguists are interested in more than language change. For example, they are interested in the speech of men and women. In some languages, men and women speak very differently: they use different pronunciations, different words, and even different grammatical endings.

Among speakers of Japanese, “stomach” is hara among men but onaka among women. Among speakers of Koasati in Louisiana, “lift it!” is lakawhol when women speak but lakawhos when men speak. English has nothing quite like this, but we too have our sex differences in speech. For a woman, a particular jumper is burgundy, while for a man it is only red. An important difference between men’s and women’s speech has been uncovered only recently by the British linguist Jennifer Coates. Coates has studied all-male and all-female conversations, and found some striking differences.

In all-male conversations, men engage in floor-holding. But women don’t do this at all. Instead, while one woman is speaking, the others constantly chip in with supporting contributions, ranging from “That’s right!” to completing the speaker’s sentence for her. This difference, naturally, leads to confusion in mixed-sex conversations. While her male partner is speaking, a woman constantly chips in with supporting remarks, in the usual female style. But the man, who is not used to this, will very likely interpret these remarks as interruptions – which they are not – and become very annoyed. This is probably why so many men sincerely believe that women interrupt all the time – whereas, in fact, observation shows that, in mixed-sex conversations, it is men who do most of the interrupting.

Variation is pervasive in language. Men don’t speak like women. Plumbers don’t speak like stockbrokers. Londoners don’t speak like Glaswegians. Students don’t speak like retired colonels. Disc jockeys don’t speak like newsreaders. Everywhere we look, we find endless variation. Even a single person speaks differently in different circumstances. With your friends in a pub, you might excuse yourself by saying “Gotta pee” – but you wouldn’t do the same while chatting politely to your mother’s elderly friends, or when being interviewed for a job with a bank. You wouldn’t write an essay or a report in the same way that you’d write a personal letter to your lover. And the people who make announcements over supermarket PA systems seem to fall back on a variety of English unknown to the rest of the population.

This variation extends not only over social groups and contexts, but also over both time and place. At various times, in various places, and in various contexts, something exceptionally good has been described within our lifetimes as ace, top-hole, spiffing, triff, tremendous, excellent, super, jolly good, awesome, smashing, wicked, fab, bodacious, unreal, and in countless other ways. One of the most striking things about our use of language is our ability to express meanings that are not really there.

Suppose several of us are planning to go to a Christmas party, and we are discussing who should drive. One person remarks, “Susie’s on antibiotics “. What is the point of this seemingly irrelevant comment? Well, of course it is not irrelevant at all. In the context, it means “Susie can drive”. Why? Because, with our experience of the world, we know that Christmas parties involve a lot of drinking, that people who drink cannot safely drive, and that people on antibiotics are usually not allowed to drink. So, in our example, Susie is a good choice of driver.

That is, in our context, the utterance Susie’s on antibiotics is interpreted to mean Susie is the obvious person to drive. Now, this is strange. Clearly, Susie’s on antibiotics doesn’t really have this meaning. But we interpret the utterance in this way anyhow, because of our knowledge of the world. The study of the way in which we extract communicative meanings from the context of utterances is now called pragmatics. We distinguish pragmatics from semantics, the study of meanings derived entirely from linguistic forms.

There are aspects of meaning that are intrinsic to linguistic forms and not merely dependent on context. The study of these intrinsic aspects of meaning is called semantics. Semantics is a surprisingly difficult topic to investigate. Take our familiar word dog. Can you write a definition of dog which will be adequate to distinguish every dog from every non-dog? This is not so easy. Suppose we try this. A dog is a four-legged animal with fur, long ears and a tail; it barks, eats meat, and lives with people. Fine. But the Mexican hairless has no fur: is it therefore not a dog? The basenji cannot bark, yet we still call it a dog. A wild dog doesn’t live with people: is it therefore a different species? No? Then why are foxes and wolves not dogs? These creatures are pretty doglike, and the fox even barks. Is a photograph of a dog still a dog? A dead dog? A stuffed dog? A cartoon dog?

It appears that we can’t define even such a simple word as dog in a rigorous way. Somehow we still seem to know what the word means and use it without difficulty. And, if dog is hard, what about defining small, green, evasive, democracy and pornography? It almost seems a wonder that we can talk to one another at all.

But words don’t have meaning only in isolation. Much of their meaning comes from the way they are connected to other words. Consider the meanings of the words took off, ran out of and lost in the following examples:

Susie took her coat off.
Susie took the coat off the peg.

Natalie ran out of the room
Natalie ran out of flour

Alice lost her toothbrush 
Alice lost her virginity

Clearly, the meanings we assign to words depend in important ways on the meanings of the other words they occur with. It is facts like these that make semantics such a difficult study to pursue.