1 Allen v. Berryhill, 27 Iowa, 534 (1869). See also Behrens v. McKen-zie, 23 Iowa, 333 (1867).

1 Per Dillon, C. J., in Allen v. Berryhill, supra. Mr. Justice Cole dis-

it nevertheless was afterwards overruled, and this maxim was established and defended both in principle and in practice, upon the ground, that, "a man cannot always remember what he did when he was out of his mind; and consequently cannot recollect whether he did this or that particular act, or entered into this or that particular contract." But although the privilege of pleading idiocy or lunacy was denied to the lunatic himself, it was always permitted to his privies in blood and in representation, that is, to his heirs, and executors or administrators, who could, after his death, avoid his contract, on the ground that he was non compos mentis.1 This distinction seems to cast a still greater absurdity over the maxim, since it seems impossible to found any such distinction upon principle. The maxim has been vigorously assailed by eminent minds in all ages. Fonblanque has declared it to be "in defiance of natural justice, and the universal practice of all civilized nations in the world."2 Lord Holt has said that "it is unaccountable, that a man shall not be able to excuse himself by the visitation of Heaven, when he may plead duress from men to avoid his own act."3 Sir William Evans affirms that "nothing could be more absurd" than this maxim;4 and Mr. Justice Story says, in relation to it, "How so absurd and mischievous a maxim could have found its way into any system of jurisprudence, professing to act upon civilized beings, is a matter of wonder and humiliation." 5 If it could prevent persons from becoming idiots or madmen, it might be of incalculable advantage, but as it never seems to have produced this result, it only stands as a useless and absurd exception to the principle, affirmed by Grotius to be a part of the law of nature, that the use of reason is the first requisite to constitute the obligation of a promise.6 The civil law, with common sense and justice, declares that "Furiosus nullum negotium gerere potest, quia non intelligit quod agit." 1

§ 76. An idiot differs from a lunatic in this, that the former is deficient, and the latter is deranged in understanding. To constitute idiocy, there must be more than mere weakness of mind, but it is not necessary that there should be an absolute absence of intellect. The rule is, that if there be such a deficiency of intelligence as to render the party incapable of understanding and acting in the ordinary affairs of life, or in the particular contract, his idiocy will annul his contract.1 It is sented; and his opinion contains an interesting and exhaustive examination of the authorities.

1 Ball v. Mannin, 3 Bligh (n. s.), 1. In this case Lord Tenterden said, "It was argued by the counsel that the party was not a lunatic, - that is, that he was not at one time of sound mind, and at another time unsound; but whatever the state of mind might be, that it was not temporary but permanent. The judge told the jury that the question was, whether the party was of sound mind or not; and that mode of stating the question was quite correct. He then proceeded to give a definition: ' That to constitute such unsoundness as should avoid a deed at law, the party executing such deed must be incapable of understanding and acting in the ordinary affairs of life.' In that, perhaps, he went too far. The judge then directed the jury that 'It was not necessary he should be without any glimmering of reason; and as one test of such incapacity, they were at liberty to consider whether he was capable of understanding what he did by executing the deed in question, when its general purport was fully explained to him.' The counsel for the defendant then required the judge to tell the jury, that in order to avoid the deed at law, the unsoundness of mind must amount to idiocy, according to the strict legal definition of an idiot; and this being refused, the bill of exceptions was tendered and sealed. It is impossible to read this record without seeing that the point of the objection is this, and this only, - that it was erroneous to direct the jury to make any other inquiry than this, whether the party was an idiot. If the judge ought so to have directed, the direction given was erroneous; but it is impossible so to contend. The jury were in substance directed to inquire whether the party was of unsound mind; and I find that the Lord Chancellor, according to the authorities, has held that a finding in these terms is sufficient. As to the strict legal definition, I find in an old book on this subject, that if a person is capable of learning the alphabet, he is not within the legal definition of idiocy; yet it is impossible to hold that persons no further qualified are capable of executing a deed. The question at law is, whether, in substance, there is such capacity of execution; and, in effect, the judge in this case so put the question to the jury, when he told them that the question was, whether the party was of sound mind or not, and directed them to consider whether he was capable of understanding the deed when explained. The observation as to the glimmering, will not make the whole direction erroneous, nor was it impossible, of course, to lay down any distinct abstract rules applicable to all cases of idiocy,-it is sufficient to invalidate any contract, if it clearly appear that the party contracting did not, at the time, understand what he was about.1

§ 77. But although mere weakness of mind is no ground of incapacity, and affords no sufficient reason for setting aside a contract, it nevertheless constitutes a material consideration in inferring fraud and unfair practice, when the contract is entirely to the disadvantage of the weaker party.2 If the contract be open to the imputation of fraud, it will be void, whatever be the character and comparative intelligence of the parties. A court of equity will vacate an agreement, where an evident advantage has been taken of a very weak-minded person, when it would refuse to set aside the same contract, if made between persons of more equal understanding.3 But this is not so much on the ground of mental incompetence, as of the force and effect of the fraud practised.4 And if no such deception were used, even a court of equity will refuse relief, inasmuch as it cannot undertake to graduate intellectual differences on a nicely adjusted scale, nor to reduce sagacity and talent to the level of weakness and folly.5