The left doesn't much like numbers. It prefers words: read in paperbacks, exchanged in cafes, bantered about in argument, issued as bureaucratic decrees by a reforming state. Numbers are for scientific or technocratic nerds, whose politics are assumed to be either autistically narcissistic or else embarrassingly utopian.

Even though the communist philosopher Alain Badiou has made numbers trendy in both Paris and London, all the truly sexy things (love itself, revolution, art, philosophy) arise for him through verbalized "events" which escape through the cracks of his bleakly nihilistic mathematical ontology.

And because money is seen as the reign of numbers it is generally disdained. As Badiou to maths, so Marx to economics: technical mastery is displayed only as a means to the triumph of linguistic authenticity. The sway of money and of numerical comparison is for Marx our seduction by quasi-religious idols. Outside monetary exchange we will at last be free to create pure human use-values and express our incomparable desires.

Less optimistically than Marx, the democratic left today mostly thinks of money as a necessary evil. This nasty material has to be used to make markets function and it has to be accumulated. But it should be reined back as far as possible: the state should confiscate the maximum amount of numbers that it can and place them safely under the control of predictable verbal orders and regulations.

But could it be that in its implicit advocacy of words over numbers the left has all too readily embraced a capitalist notion of the nature of money? This notion assumes that money is necessarily a commodity - whether valid or illusory, as it was for Marx - and that the pursuit of wealth consists in piling the stuff up as high as possible.

For this view the pre-monetary accumulation of things through barter and gift-exchange was a primitive approximation to the role of money. Only money gives the individual the power to amass the goods and leverage that he wants.

But were money really like that, then surely capitalists would compete to establish rival mints or a monopoly over the money supply, just as they once competed to pile up gold, when the medium of exchange was still secured on something taken to be valuable in itself? And in that case the coining role of the state would not be necessary.

But just because it is always necessary, one can suggest an inversion of historical teleology: gift-exchange is not a primitive substitute for money; rather money is a more developed, highly sophisticated form of constructing the social through the obligation to give, receive and return gifts.

For when I eat a meal in a restaurant, this is no pure economic swap in which (except in dire emergency) I supply the owner with my suit jacket or offer to do the washing-up in bartered exchange. Rather, it is as if she has made me a meal as a gift, and in exchange I supply her, not with an equivalent commodity, but merely a bit of paper, or today just some numbers which are nothing more than a guarantee that legally-underwritten society in general will now, at some point in the future, supply her with a kind of equivalent counter-gift on my behalf.

From this example we can see that the very fact of centralized state monopoly on minting implies that the assumed rationale of money is to do with the reciprocally balanced meeting of needs. It is not inherently a commodity, but rather a system of numerical signs for facilitating and measuring mutual exchange, as Judaism, Christianity and Islam have all traditionally pointed out.

But today the right and the left in their wake tend to ignore this reality, and to denature money by treating it as if it were not embedded in a social as well as an economic contract. We wrongly assume that a monetary profit made through a transaction confers upon the profiteer a kind of independent coercive power to impose more of his will in the future - as if money promoted its own self-motion, like atoms in irreversible Newtonian space.

We thereby forget that the profit made is in principle only a socially-underwritten guarantee of rights to "return gifts" of a roughly equivalent value to those of products and services received.

Of course, our current market capitalism works by subverting the natural reciprocity of money through the constant accumulation of excessive profit made at the expense of both workers and consumers. Once profit has been disembedded from the cycle of reciprocity (even though this process can never be entirely carried through, since it denies money's true nature) it can then indeed economically override the implicitly assumed social contract.

Moreover, the new dominance of finance capital means that banks increasingly invite an indebtedness (of themselves, of governments, of individuals) that can never be met. Thereby, in effect, they do act as if they were competing quasi-mints, and eventually force the real mints to print ever more money, today unsupported by any concrete measure of real material wealth.

However, this denial of the real nature of money engenders, as we now see, both constant economic crisis and a denaturing of markets which renders them the coercive instruments of small oligarchic elites and no longer genuine processes of free exchange.

Yet by reminding ourselves of the true nature of money we can better see how the left can work with and not against the natural grain of markets.

To ignore this point is to invite continuing long-term impotence and a cycle of gradually receding egalitarian gains. Thus if the socialists win the next presidential election in France, then another round of etatisme might produce temporary improvements for ordinary people and yet still lead, as under Mitterand, quickly to a loss of market confidence, excessive inflation and an increase in public indebtedness. For a short while the terrible tide of numbers would have been held back, but soon it could well roll in again with a yet more unconstrained force.

By contrast, any really permanent gains on the left require a reform of the operation of markets themselves. The key to such a reform is persuading the very owners of capital that social and ethical value, including the more equitable distribution of resources, works to promote and not to inhibit truly stable and sustainable wealth-creation.

For if money is properly the essential means and measure of the social exchange of gifts and services once one has a division of labour, then there is no reason to restrict the negotiation of economic contracts merely to a compromise between independent self-interests. Nor do we therefore need to wait for "political" words later to come along to modify sheerly "economic" numbers.

Instead, words can be exchanged along with numbers and in harmony with them, in a process of "civil economy." What I mean by this is that every contract can also consider "shared benefit," or the promotion of the wider social, educational and environmental circumstances of the contracting parties. This can be done out of a combined moral concern for the world in which both parties have to live, and at the same time for reasons of long-term, more secure business reliability.

Such mutual promotion would be likely to produce a much stronger sense of equitable "just prices" and "just wages" than we have at present. After all, even under our current system a tacitly recognised cultural sense of the crucial right of all to food prevents to some degree (at least in Europe) a sheerly capitalistic exploitation of the threat of starvation, seasonal shortages and poor diet.

But under a drastic extension of shared benefit, numerical equivalences and proportions of value would start much more to correspond with the ethical values that we express through words.

Moreover, the state monopoly of minting can itself be linked to this conjuncture, in a way that can also partially decentralize the monetary function. For instead of an "occasional" and top-down operation of prices and incomes policy, we need in future a more consistent operation of courts and regulative bodies at every level in order to ensure, in the face of abuse, reasonably just instances of prices, wages, interest and profits.

As far as possible these things should be achieved extra-legally through the creation of a newly honourable business ethos and a new "trade" in just that honour, which is therefore itself subject to "market discipline" - the natural checks of supply and demand.

However, because money itself is a state and legal institution, the left should not baulk at an ultimate role for legal intervention in this sphere. And mediating between the courts and internal ethos, professional associations and trades unions can start to play a revived "guild-type" function.

So if we are, in the long-term, to turn the often made call for an ethical market into reality, the left, while sustaining its proper love of words, needs to start counting.

John Milbank is Research Professor of Politics, Religion and Ethics at the University of Nottingham, Director of the Centre of Theology and Philosophy, Chairman of the ResPublica Trust and a Fellow of the Contextual Theology Centre.