Where a non-variation clause and a whole agreement clause were included in a comprehensive contract dealing in detail with the subject matter between the parties, the court refused to import a tacit term into the contract.
A tacit term is an unexpressed provision in the contract which derives from the common intention of the parties and which is inferred from the express terms of the contract and the surrounding circumstances.
The courts are generally slow to import a tacit term especially if there is a comprehensive agreement and the term is not necessary to give the contract business efficacy. This test is also applicable to the importation of an implied term.
The plaintiff was a third party who failed to import a tacit term in his favour into a contract between two other parties.
This was, by the way, yet another case where evidence was led in court to establish the intention of the parties whereas such evidence is inadmissible and considerable costs were no doubt wasted on the endeavour.
The case is Adhu Investments v Padayachee.