Mistake

1. Mistake By James Prior

2. A contract which is well formed, but where one or both parties made some fundamental false assumption in forming it, is said to be made under a mistake. There are four main categories concerning mistake: Common mistake- where parties are labouring under the same false assumption; Mutual mistake- where the parties are at cross purposes; Unilateral mistake- where only one party is mistaken and the other is aware of this; Mistake over documents

3. Common mistake is where the parties are in agreement, but make the same false assumption in forming a contract, so their contract is based on a situation which is false Two main groups have arisen this way: Cases where the mistake is over the existence of the subject matte; Cases where mistake is over the quality of the subject matter.

4. Where the subject matter is non-existent

6. Mistake over title

7. Mistake over quality of subject matter

9. Mutual Mistake

10. Unilateral mistake

14. Mistake relating to documents

15. The relationship between mistake and frustration Mistake occurs before or at the point of the contract, but frustration occurs during the lifetime of a contract; Property Co Ltd v John Walker and Sons Ltd. Purchaser of building mistaken over value as building was �listed� and therefore subject to restrictions. Had the �listing� taken place before the contract the claim could may have succeeded in mistake, but in fact the �listing� occurred after the point of the contract.