Would you like fries with your greeting?

This collection of essays, from an Oxford conference on "English language, the media and global communication", examines the many forces acting on our language in our time. In doing so, it sheds light on the way language develops in all societies and times.

Take the example of McDonald's, which, like many modern companies, has discovered that customer relations is a major factor in competition, and trains its employees to address customers in a particular register shown to satisfy. The idiom has emerged from close study of employee-customer interactions. McDonald's modes of address feed into a wider set of changes, all reflecting the successful exploitation of new ways to address customers seeking hamburgers. A change in social-economic relationships, reflected in the language of address, travels around the globe and, as McDonald's moves from one society to another, it spreads the lessons it has learnt in Chicago to Budapest and Beijing, Bradford and Bangalore. The linguistic innovations it has pioneered spread through the service industries from language to language.

Another comparable modern institution impacting on the language is the talk show, particularly the US variety that is sold around the world and spawns myriad imitators. The Oprah Winfrey Show becomes a globally available style of discourse. The open and sincere discourse of the talk show spreads its ideology along with its linguistic forms. In their time, classical literary forms spread through biblical discourse in a similar way. Today, the mass media and mass marketing have taken over and become the chief "focusing agents" - the catalysts of linguistic variation.

While good customer relations give rise to a new civility and emotional openness, there is also a new discourse of incivility, an openly virulent language. One of the essay writers ascribes this to the inclusion of new groups in public political discourse; the coarse displays of non-standard English on US television are the results of democracy rather than incivility or, rather, we are witnessing the linguistic outcome of the ousting of middle and upper-class white males from their monopoly of language control by other classes and ethnic groups.

I am not convinced since "arriving" ethnic groups generally find their way into traditional discourse modes as they prosper in the new environment.

But the essay on "The new incivility" points eloquently to the many more agents of change we have today, possessing new access to the levers of linguistic authority.

The contributors are drawn from surprisingly diverse sources: the essay on wine language, for example, shows how inadequate English is for conveying ideas of difference between wines. As wine slipped out of the control of a single social class (wine drinking has shifted from 4 per cent to 70 per cent of the UK population in half a century), the floodgates opened for a new linguistic preposterousness of "winespeak" as a host of wine journalists attempted the impossible task of describing taste, harnessing new ranges of metaphor.

Another essay, on modern political language, traces the new trade of political spin to its ancestral roots in classical rhetoric; spin is, after all, a version of truth put forward by a professional in an adversarial environment with a robustness intended to enable it to survive.

One writer examines the normative function of the television talk show Kilroy in the representation of parenting, teaching viewers how to fix their lives in socially acceptable ways - "emotional DIY", as he calls it.

Host Robert Kilroy-Silk ensures, through his control of the floor, that the representations of parenting conform to preordained values, with which the audience is brought to collude.

But is not the very idea that one must communicate to live, itself a deeply value-laden, ethnically bound product of the globalised world, normative to the point of oppression? The most powerful instructors of language in the new global culture are not grammarians or lexicographers but people with expertise in psychology, therapy, counselling, social work, customer service - the whole diversity of modern caring professionals, the pedagogues of the service industries.

These have a shared message, which Deborah Cameron codifies fascinatingly in her essay: reticence and indirectness have come to represent a lack of openness, and an egalitarian candour has become the obligatory mode even in job interviews and adult-child discourse. Conflict is treated as if it can arise from misunderstanding only, rather than be a natural outcome of divergence of interests; a pervasive emphasis is placed on the ability to verbalise one's feelings - "sharing" our emotions has become the touchstone of honesty itself.

Judgements on language use have thus acquired a moral dimension. "Silence or emotional inexpressiveness indicates a closed, ungenerous person; indirectness is manipulative; formality is indicative of authoritarian attitudes; arguing or disagreeing is aggressive." I recommend this collection to anyone interested in the subtle links between the global economy and the intimacies of personal expression.

Anthony Smith is president, Magdalen College, Oxford.