Sheewin, C. J.
1. Will contest; disqualification of judge. John P. Glass died on the 14th day of February, 1900, and on the 22d day of the same month an instrument purporting to be his will was filed for probate. Objections thereto were filed "on the 20th day ** . .. of March, 1900. A part of the .land of which Mr. Glass died seised had come to him through a conveyance from John Podge to his wife, Eliza A. Glass, and after the death of Mr. Glass, and after the contest over his will had arisen, as we understand the record, an action was brought by some of the contestants herein claiming title to a portion of the land so conveyed by John Dodge to Eliza A. Glass, and asking a partition thereof on the ground that Eliza A. Glass took only a life estate under the deed. Elickinger Bros., of Council Bluffs, Iowa, were the plain*648tiffs’ original attorneys in the partition suit. At that time Judge Preston was a member of the law firm of Preston, Grimm & Moffit, of Cedar Rapids, Iowa, in the county where the suit was to be brought. After some correspondence between Flickinger Bros, and Mr. Grimm, an original notice in that action was drawn by Judge Preston and signed “ Flickinger Bros, and Preston, Grimm & Moffit,” and the petition in the case bore the same signature. Before the issues were finally settled, however, Judge Preston was elected to the district bench, and his name did not appear further as an attorney in the case. As a matter of fact, he had never consulted with any one about the merits of the case, and knew nothing thereof, and the record shows conclusively that his firm’s connection therewith was at that time, at least, only nominal, and for the accommodation of Flickinger Bros. The proponents objected to trying the instant case before Judge Preston on the ground that he was disqualified under section 284 of the Code, which disqualifies a judge where he has been attorney for either party in the action or proceeding, and it is now insisted that Judge Preston should not have tried the case. This is clearly not the same action or proceeding that Judge Preston’s firm appeared in, and under tire strict letter of the statute he was clearly not disqualified from hearing this case. If the precise issue presented here had in fact been a material issue in the partition case, and if Judge Preston’s firm had been attorneys therein in fact, instead of nominally only, it might be said that the spirit of the statute is broad enough to disqualify. But it does not appear that the validity of the will in question could have been controlling in the other case. As we understand the record, the plaintiffs’ claim there was that the deed from John Dodge to Eliza A. Glass conveyed only a life estate, and a determination of that question in no way involved the validity of John P. Glass’ will.
*6492. Mental capacity: evidence. *648Over the objections of the proponents, the court per*649mitted nonexpert witnesses to testify that shortly before the execution of the will, and at about the time that it was executed, the deceased was of unsound mind, and incapable of intelligently transacting business or disposing of his property. While undue influence was charged, as well as incapacity, the real contest was on the latter ground; and there was evidence tending to show that the incapacity amounted to senile dementia, and had existed for a long time before the will was executed. The ultimate question for the jury to determine was whether the testator had sufficient mental capacity to dispose of his property by will at the time the instrument was executed, and this precise • question was, in effect, answered by the witnesses to whose testimony we have referred.
So far as the questions and answers related to the time of making the will, or to a time so closely approximating thereto as to' amount to the same thing, there was error in receiving the testimony, for the reason that the ruling permitted the witness to testify, in effect, that the testator was capable of making the will in question, and such testimony is incompetent under the rule of our own decisions and by the weight of authority. Pelamourges v. Clark, 9 Iowa, 1. But other questions of the same kind related to the testator’s capacity at a time prior to the execution of the will, and the testimony so elicited, we think, was competent. Personal acquaintance, contact, and observation disclose the mental characteristics of persons, and from this association we form jridgments as to the mental capacity of those with whom we come into such close relationship. A person may be entirely sound mentally on all subjects save one, and as to that particular subject his mind may be so diseased as to render it impossible to say that he is of sound mind. If a witness who is called t'o testify as to mental capacity is confined to the bare statement or conclusion that- the person was either sane or insane, the answer is practically valueless as evidence of his capacity to do a certain act. But if the witness may *650give bis opinion as to tbe mental capacity touching tbe precise trait involved it affords material belp to tbe jury or other trier. Tbe true mental condition of a person cannot be understood by tbe trier unless tbe degree of bis capacity be in some way disclosed. And tbe opinion of tbe witness that tbe person was capable of transacting ordinary business, and of intelligently disposing of property, is no more than a statement of bis opinion as to his real mental condition. Hayes v. Candee, 75 Conn. 131 (52 Atl. 826). And see further, supporting this rule, Keithley v. Stafford, 126 Ill. 507 (18 N. E. 740); Schneider v. Manning, 121 Ill. 386 (12 N. E. 267); U. S. v. Guiteau, 47 Am. Rep. 247; Ring v. Lawless, 190 Ill. 520 (60 N. E. 881); Jones v. Collins, 94 Md. 403 (51 Atl. 398); Poole v. Dean, 152 Mass. 590 (26 N. E. 406); Pinney’s Will, 27 Minn. 282 (6 N. W. 791, 7 N. W. 144); Horah v. Knox, 87 N. C. 483; State v. McGruder, 125 Iowa, 741. Betts v. Betts, 113 Iowa, 111, seems to announce a different rule, based on tbe case in 9 Iowa, supra. But that case did not go further than to bold that tbe testimony as to tbe capacity to make tbe will in question was incompetent. Tbe Betts Case was in fact practically overruled in the case of State v. McGruder, supra.
3. Undue influence: submission of issue. It is most earnestly contended that there was no evidence of undue influence, and that tbe court erroneously submitted that question to tbe jury. It is. seldom that such influence is capable of direct proof, and in cases x . -where incapacity and undue influence are both relied upon to defeat tbe will, and there is .substantial evidence of tbe testator’s unsoundness of mind, any evidence, however slight, tending to prove tbe issue of an undue influence is freely admitted. Tbe facts here are such that we cannot say, as a matter of law, that just inferences of such influence may not be drawn therefrom. If it be true that tbe testator was afflicted with senile dementia at tbe time be executed tbe instrument, be may have been easily influenced by those of his children who were with him *651constantly, and wbo were present and assisted bim in signing a will that bad been prepared at tbeir direction when be was not present. Page on Wills, section 414, and cases cited.
4. Construction. Tbe question whether the trust deed previously executed 'was a part of tbe will was a question of law for the court, and tbe court'properly refused to submit it to tbe jury.
5. Evidence: declaration of decedent. Tbe court erred, however, in instructing that it could only be considered on tbe question of tbe testator’s mental’ capacity at tbe time be executed the will. Tbe trust deed was made about three years before tbe will, and at a time when tbe testator was concededly in possession of bis mental faculties, and was probably’not under tbe influence of others. It was therefore competent as a written declaration of tbe decedent. In re Estate of Goldthorp, 94 Iowa, 336; Dye v. Young, 55 Iowa, 433; Bever v. Spangler, 93 Iowa, 576.
6. Mental in capacity: presumption; burden of proof. Tbe trial court also instructed, in effect, that if tbe deceased was afflicted with what is known as senile dementia, affecting bis capacity to make tbe will, tbe presumption would be that such condition continued up to tibe "time that the will was' made, and that tbe ]31;irc[en 0f pr0of would then be on the proponents to show a lucid interval at tbe time of tbe execution of tbe will. This instruction we think wrong, because there was testimony before the jury tending to show that senile dementia was not necessarily a settled condition of the mind that would render tbe testator incapable of intelligently executing tbe will. The rule of law is that primarily every person is presumed sane until tbe contrary is proved, and it is also true that when unsoundness of mind is proved to exist and to be settled a presumption then arises in favor of its continued existence; but in this ease no instruction was given by tbe trial court embodying this thought, and we think that it should have instructed tbe jury that they *652must find a continued and settled mental unsoundness before indulging in the presumption stated by the court. Kirsher v. Kirsher, 120 Iowa, 337.
A great many other alleged errors are argued, but as none of them appear to be of consequence, and as tbe same questions are not likely to arise on another trial of the case, we need not notice them further than .to -say that we find no reversible error, unless it be in the cross-examination of Mrs. Madison as to a letter written by her, and in the attempted impeachment of Mrs. Murphy without first having laid a proper foundation therefor.
Nor the errors discussed the judgment must be reversed. The motion to tax the costs of the appellee’s abstract to them is sustained, and the motion to tax a part of the appellants’ abstract to them is sustained to the extent of taxing the cost of one-fifth thereof to the appellants.— Reversed.