A Tale of Too Many Doctrines: Supervening Impossibility and the Sale of Goods

Contracts for the sale of goods contain three default rules addressing the problem of supervening impossibility: sections 7 and 20 of the Sale of Goods Act 1979 and the doctrine of frustration. This article uses a legal historical method to examine why this is the case and what the relationship between these rules is. It contends that the current approach is the accidental result of a series of historical contingencies and argues that it is unsatisfactory for several reasons. It then offers suggestions as to how the law might be rationalised. On a broader level, the inquiry provides a lens through which the wider history of supervening impossibility in English contract law can be explored. The article argues that our current conceptualisation of the law prior to 1863 is fundamentally flawed, and that this inhibits our understanding of how the earlier law both shaped and confused the development of a more general doctrine of supervening impossibility.