Chapter 10 analyses Locke’s early writings on money within the wider context of his corpuscularism and explores what I have termed his ‘doctrine of necessities’. The chapter argues that his theory concerning the ‘necessaries’ and ‘necessities’, rather than ‘rights’, gives systematic coherence not only to his political and economics writings but to his entire philosophical theory. In Locke’s early writings on money, the key issue concerns economic phenomena that belong to an interdependent scientific system. The chapter discusses in detail the literature dealing with moneylending that existed before Locke and demonstrates in this manner his originality.