Deemer, C. J.
1 — The execution of the contract, the payment of a part of the consideration, and a tender of the remainder, are all admitted. The sole issue in the case relates to appellant O’Brien’s condition of mind at the time he entered into the contract. The contract was made on November 14, 1894. On the twenty-second day of the same month, O’Brien was Taken before the board of inisane commissioners of Howard county, adjudged insane, and taken to the lum-ital at Independence, from which place he bias never been discharged, so far as shown. The contention now made in his behalf is that he was so far demented and nnsound of mind at the time the contract was made that it should not be enforced. This is almost wholly a. question of fact, and a discussion of the evidence adduced would accomplish no useful purpose1. The presumption is that he was sane When the contract was made, and the burden is upon the appellants to show that he was not, and that he was in fact incapacitated from making the contract. In order to avoid the contract, it must appear, not only that defendant was unsound of mind, or insane, when it *241was made, but that this unsoundness or insanity was of such character as that he had no reasonable perception or understanding oí the nature and terms of the contract. Mere weakness of mind, or unsoundness to some degree, is not sufficient, in the absence of fraud or undue influence, to invalidate a contract. Campbell v. Campbell, 51 Iowa, 713; Burgess v. Pollock, 53 Iowa, 273. The doctors who have charge of O’Brien at the hospital ,say that he had partial or primary dementia when he came to that institution, and that this disability probably existed at the time the contract was entered into. That O’Brien was, and had been for many years prior to the making of the contract, peculiar in Ms methods and conduct, is conceded. But we find that he looked after hi® business affairs with judgment and discretion, and exercised at least an ordinary degree of foresight and intelligence in all his dealings. The contract is entirely free from fraud o>r undue influence, and the consideration agreed to be paid is not inadequate. We 'are constrained to believe that O’Brien fully understood and comprehended the nature and effect of the transaction, and that while hi® mind was to some extent unbalanced, and be was •troubled with partial dementia, yet he had that judgment and discretion, that understanding of the effect of the agreement, that he should be held bound thereby. After O’Brien was taken to the hospital, he wrote two letters, referring to business matters connected with his farm, and to the contract which is at the bottom of this controversy, which clearly indicate that he was possessed of memory and understanding, and was qualified to judge of the care his property needed, and of the effect of Ms contract with appellee. These letters afford strong evidence of appellant’s competency to transact business. Without referring more in detail to the evidence before ns, it is sufficient to say that we *242are all agreed in holding that there is no such showing of incompetency as will justify a court in denying the relief asked. Suggestion is made in argument that the contract is ambiguous, and that the consideration is inadequate. Neither of these claims are of sufficient merit to justify extended, consideration. They are folly answered by what is said in the case of Throckmorton v. Davidson, 68 Iowa, 643. The decree of the district court is affirmed.