Report No. 59
3.10. Position at common law-two aspects.-
An analysis will reveal that there are two ideas which underline the approach of the common law towards capacity to exercise legal powers. First, there is the insistence upon the necessary state of mind to transact the business or legal act in question (the relevant state being dependent upon the exact nature of the business or act). Secondly, there is the proposition that soundness of mind is based upon ability to manage oneself and one's affairs. This approach clearly stated in an English case1 where it was said that the question for decision was whether a person was of perfectly sufficient soundness of mind to form a valid contract of marriage. "If the incapacity be such," said Sir John Nicholl, in another case2, "that the party is incapable of understanding the nature of the contract itself and incapable, from mental imbecility, to take care of his or her own person and property, such an individual cannot dispose of her person and property by the matrimonial contract, any more than by any other contract."3
1. McAden v. Walker, (1813) 1 Dow 148.
2. Browning v. Beane, (1812) 2 Phill 69 (70, 71): 161 ER 1080.
3. c f. Sir William Scott, in Turner v. Metiers, (1808) 1 Flag Con 414 (418): 161 ER 600.