What is the basis of English Common law ?
English law clearly recognises at least the following unjust factors : Mistake of fact Mistake of law Duress Undue influence Total failure of consideration Miscellaneous policy - based unjust factors such as " withdrawal within the " locus poenitentiae "" It is at least arguable that English law also recognizes the following unjust factors , but some controversy surrounds each : Ignorance / powerlessness Unconscionability Partial failure of consideration Absence of consideration " Absence of consideration " is particularly controversial because the cases that support its existence as an unjust factor can also be used to support the view that English law has begun to favour the " absence of basis " approach .