This chapter explores Simmel's definition of money as a ‘claim upon society’ in The Philosophy of Money. Specifically, I ask whether this description provides any analytical purchase on money during an era when, first, the relevance of the notion of ‘society’ is being contested across several different areas of sociology, and second, money has assumed a wide range of new forms whose connections with ‘society’ in any conventional sense are increasingly difficult to discern. My discussion will consider these two issues together. In relation to the first, I will examine Simmel's statement in conjunction with a range of different treatments of ‘society’ and ‘the social’ in his work: from the idea of nation- state that is sometimes implied in the second chapter of The Philosophy of Money, through the more abstract ideas of society (such as the ‘perfect’ society) found in Sociology to the ‘vitalist’ conceptions of the social that feature in his later works. I will then seek to apply these varying conceptions of the relationship between money and ‘the social’ by asking what insights Simmel's work offers for investigating the increasingly complex world of disintermediated money: from social credit, through complementary currencies, to new forms of digital money. Of these, one of most intriguing – and problematic – is Bitcoin, whose motto is ‘Vires in Numeris’ (‘Strength in Numbers’), and whose designers claim to have dispensed with the very feature of money which figures at the heart of Simmel's own conception, namely, its reliance on mutual trust. I ask whether the apparent success of Bitcoin now means that Simmel's original description of money must be reconfigured in light of money's increasing dependence on machines.

This chapter has three main sections. First, I argue that the roots of today's changing world of money can be traced back to key changes that took place during the 1970s, particularly the collapse of the Bretton Woods system. These changes were ultimately responsible for the decline of monopoly national currencies, and provide the context for understanding the potential significance of Bitcoin. Second, I discuss Simmel's conception of money as a ‘claim upon society’, and examine what it potentially means in light of various interpretations of the term ‘society’ in his work.