UNILATERAL
MISTAKE
One
party to the contract only is mistaken as to the terms, offer or
acceptance, or the other party's identity. If the other party knows
or ought to have known of the mistake the contract is void
Cundy v Lindsay. In theory the contract should be void as
there is no real agreement but the actions of the party and evidence
of the contract may be such as a reasonable man would infer
agreement.
See
mistake.