Of pragmatism and principle
From Farah Constructions Pty Ltd v Say-Dee Pty Ltd HCA 22 at §154 (joint judgment of Gleeson CJ, Gummow, Callinan, Heydon and Crennan JJ)
The restitution basis reflects a mentality in which considerations of ideal taxonomy prevail over a pragmatic approach to legal development. As Gummow J said in Roxborough v Rothmans of Pall Mall Australia Ltd (2001) 208 CLR 516 at 544 [72].
"To the lawyer whose mind has been moulded by civilian influences, the theory may come first, and the source of the theory may be the writings of jurists not the decisions of judges. However, that is not the way in which a system based on case law develops; over time, general principle is derived from judicial decisions upon particular instances, not the other way around."