Equity and Opportunism in the law of contract – A Case Study in Fusion by Diffusion
Tan Zhong Xing
(2018) 30 SAcLJ 305
In recent years, the debate over the fusion of law and equity has been reinvigorated. One significant contribution comes from Harvard Law School’s Professor Henry Smith, who has argued that equity displays a distinctive opportunism-countering function, serving as a “second-order safety valve”, which arrests opportunistic conduct ex post via tailored standards, assisted by various proxies and presumptions. The purpose of this article is to explore Smith’s “opportunism thesis” in the context of contract law, with particular reference to the doctrines of duress, undue influence and unconscionability. The present author argues that the opportunism thesis is a promising account of the doctrinal architecture of these vitiating factors, while emphasising that the recognition of such an “equitable” function does not necessarily point in an anti-fusionist direction. On the contrary, the author argues that the evolution of the “anti-opportunism” idea has tracked a narrative of “fusion by diffusion” – a process by which equity’s original “anti-opportunism” function has travelled across the common law–equity jurisdictional divide in a highly interactive manner, generating doctrinal transplantation and cross-fertilisation.