The financial crisis that exploded in autumn 2008 has rearranged the dominant views of capitalism and socialism. Until recently, any critique of neoliberal strategies of deregulation, privatisation and the reduction of welfare structures – let alone of capital itself – was cast in the dominant media as crazy talk. In early 2009, however, Newsweek proclaimed on its cover, with only partial irony, "We are all socialists now". The rule of capital was suddenly open to question, from left and right, and, for a time at least, some form of socialist or Keynesian state regulation and management seems inevitable.

We need to look, however, outside this alternative. Too often it appears as though our only choices are capitalism or socialism, the rule of private property or that of public property, such that the only cure for the ills of state control is to privatise and for the ills of capital to publicise, that is, exert state regulation. We need to explore another possibility: neither the private property of capitalism nor the public property of socialism but the common in communism.

Many central concepts of our political vocabulary, including communism as well as democracy and freedom, have been so corrupted that they are almost unusable. In standard usage, in fact, communism has come to mean its opposite, that is, total state control of economic and social life. We could abandon these terms and invent new ones, of course, but we would leave behind too the long history of struggles, dreams and aspirations that are tied to them. I think it is better to fight over the concepts themselves in order to restore or renew their meaning.

One of the reasons that the communist hypotheses of previous eras are no longer valid is that the composition of capital – as well as the conditions and products of capitalist production – have altered. How do people produce both inside and outside the workplace? What do they produce and under what conditions? How is productive cooperation organised? And what are the divisions of labour and power that separate them along gender and racial lines and in the local, regional, and global contexts?

Since the middle of the 19th century large-scale industry held the hegemonic position within society, not in the sense that most people worked in factories (in fact, a small percentage did, even in the dominant countries) but rather in that the qualities of industry were progressively imposed over other economic sectors and eventually over society itself. Today, however, it is clear that industry no longer holds such a hegemonic position. This is not to say that fewer people work in factories today than 10 or 20 or 50 years ago – although, in certain respects, their locations have shifted, moving to the other side of the global divisions of labour and power. The claim, once again, is not primarily quantitative but qualitative. Industry no longer imposes its qualities over other sectors of the economy and over social relations more generally. That seems to me a relatively uncontroversial claim.

More disagreement arises when one proposes another form of production as successor to industry and dominant in this way. Toni Negri and I argue that immaterial or biopolitical production is emerging in that hegemonic position – the production of ideas, information, images, knowledges, code, languages, social relationships, affects and the like. This designates occupations throughout the economy, from the high end to the low, from healthcare workers, flight attendants and educators to software programmers; and from fast food and call-centre workers to designers and advertisers. Most of these forms of production are not new, of course, but the coherence among them is perhaps more recognisable and, more important, their qualities tend today to be imposed over other sectors of the economy and over society as a whole. Industry has to informationalise: knowledge, code and images are becoming ever more important throughout the traditional sectors of production; and the production of affects and care is becoming increasingly essential in the valorisation process.

Marx recognised, parallel to the rise to dominance of industrial production, a struggle between two forms of property: immobile property (such as land) and moveable property (such as material commodities). Today, with the rise of the biopolitical economy, the struggle is between material property and immaterial property. Or, to put it another way, whereas Marx focused on the mobility of property, today at issue is scarcity and reproducibility, such that the struggle is between exclusive versus shared property. Consider, for example, debates over patents, copyrights, indigenous knowledges, genetic codes, and the information in the germplasm of seeds. Just as Marx saw that movement necessarily triumphs over immobility, so too today the immaterial triumphs over the material, the reproducible over the unreproducible, and the shared over the exclusive.

The emerging dominance of this form of property is significant, in part, because it demonstrates and returns to centre stage the conflict between the common and property as such. Ideas, images, knowledges, code, languages and even affects can be privatised and controlled as property, but it is more difficult to police ownership because they are so easily shared or reproduced. There is a constant pressure for such goods to escape the boundaries of property and become common. If you have an idea, sharing it with me does not reduce its utility to you, but usually increases it. In fact, in order to realise their maximum productivity, ideas, images and affects must be common and shared. When they are privatised their productivity reduces dramatically – and, I would add, making the common into public property, that is, subjecting it to state control or management, similarly reduces productivity. Property is becoming a fetter on the capitalist mode of production. Here is an emerging contradiction internal to capital: the more the common is corralled as property, the more its productivity is reduced; and yet expansion of the common undermines the relations of property.

Neoliberalism has been defined by the battle of private property not only against public property but also, and perhaps more importantly, against the common. Two types of the common have been the object of neoliberal strategies of capital. On the one hand, the common names the earth and all the resources associated with it: the land, the forests, the water, the air, minerals and so forth. On the other hand, the common also refers, as I have already said, to the results of human labour and creativity, such as ideas, language, affects and so forth. One major scene of such privatisation has been the extractive industries, providing transnational corporations with access to diamonds in Sierra Leone or oil in Uganda or lithium deposits and water rights in Bolivia. Many authors, including David Harvey and Naomi Klein, have described this in terms that mark the renewed importance of primitive accumulation or accumulation by dispossession.

The neoliberal strategies for the privatisation of the "artificial" common are much more complex and contradictory. The more the common is subject to property relations, as I said, the less productive it is; and yet capitalist valorization processes require private accumulation. In many domains, capitalist strategies for privatising the common through mechanisms such as patents and copyrights continue (often with difficulty) despite the contradictions. The music industry and computer industry are full of examples. This is also the case with so-called biopiracy, that is, the processes whereby transnational corporations expropriate the common in the form of indigenous knowledges or genetic information from plants, animals and humans, usually through the use of patents. Traditional knowledges of the use of a ground seed as a natural pesticide, for instance, or the healing qualities of a particular plant, are turned into private property by the corporation that patents the knowledge. (Piracy is actually a misnomer for such activities. Pirates have a much more noble vocation: they steal property. These corporations instead steal the common and transform it into property.)

The development of capital is clearly not good in itself – and the tendential dominance of immaterial or biopolitical production carries with it a series of new and more severe forms of exploitation and control. But we should also recognise how biopolitical production, particularly in the ways it exceeds the bounds of capitalist relations and constantly refers to the common, grants labour increasing autonomy and provides the tools or weapons that could be wielded in a project of liberation. .

This notion of the common can help us understand what communism means – or what it could mean. Marx argues in his early writings against any conception of communism that involves abolishing private property only to make goods the property of the community. Instead communism properly conceived is the abolition not only of private property but of property as such. It is difficult, though, for us to imagine our world and ourselves outside of property relations. "Private property has made us so stupid and one-sided," he writes, "that an object is only ours when we have it." What would it mean for something to be ours when we do not possess it? What would it mean to regard ourselves and our world not as property? Has private property made us so stupid that we cannot see that? Marx tries to grasp communism, rather awkwardly and romantically, in terms of the creation of a new way of seeing, a new hearing, a new thinking, a new loving – in short, the production of a new humanity.

Marx here is searching here for the common, or, really a form of biopolitical production put in the hands of the common. The open access and sharing that characterise use of the common are outside of and inimical to property relations. We have been made so stupid that we can only recognise the world as private or public. We have become blind to the common. Communism should be defined not only by the abolition of property but also by the affirmation of the common – the affirmation of open and autonomous production of subjectivity, social relations, and the forms of life; the self-governed continuous creation of new humanity. In the most synthetic terms, what private property is to capitalism and what state property is to socialism, the common is to communism.

• This is an edited version of an essay by Michael Hardt in The Idea of Communism, published by Verso Books