正在編輯用戶:Hinnia/Mistake （章節）

== Introduction ==

=== Definition and Nature ===

* A contract may be held defective
** If one or both parties enter into it under some misapprehension or misunderstanding
** But would not have done so had they known the true position.
* Objective approach to agreement (What a reasonable person would infer from conduct)
** Mere subjective mistake is insufficient to set a contract aside.
* Central Policy Tension
** Law must balance certainty in transactions (favouring a narrow doctrine) 
*** Against the desire to protect a party from a bargain radically different from what was intended (favouring a wider doctrine).
* Terminological Confusion: Terms are used inconsistently.
** Common Mistake: Both parties make the same mistake (e.g., both believe a painting is an original).
** Unilateral Mistake: Only one party is mistaken.
** Mutual Mistake: Both parties are mistaken, but about different things (they are at cross-purposes). This term is ambiguous and often avoided.
* Key Distinction: Void vs. Voidable
** Void (ab initio): Contract is a nullity from the start
*** Produces no legal effects.
*** Crucial for third-party rights (if A's contract with B is void, B gets no title and cannot pass title to C).
** Voidable: Contract is valid until the aggrieved party chooses to set it aside (e.g., for fraud).
*** Until avoided, a rogue can pass good title to an innocent third party.

==== Brennan v Bolt Burdon [2004] EWCA Civ 1017 ====

* Establishes that for common mistake to void a contract,
* Mistake must render the contract impossible to perform.
* Mistake about the state of the law (e.g., the effect of a court judgment) does not necessarily satisfy this test if the contract remains performable.