Mistake, Failure of Consideration and the Planning Theory of Intention

This paper seeks to begin an important project of examining in philosophical terms the unjust factors present in 'failure of consideration' and 'mistake' claims. There has been considerable work done to rationalise the doctrinal foundations of unjust enrichment, but there has been much less examination of the philosophical basis or structure of the different unjust factors. Such an examination is long overdue. There are clear structural and analytical differences among these factors.