ON PETITION FOR REHEARING.
(No. 2767;
*193OPINION
PER CURIAM.Defendant has filed a petition stating various reasons why a rehearing should be granted. We are impressed now as we were in the initial presentation of the case by counsel’s ability, industry, and sincerity. Accordingly, any nonconcurrence with defendant’s views on certain phases of the case arises because of the inherent difference of human viewpoint and the inevitability that in every case courts must disagree with and discard the position taken by one or the other of the litigants. Our analysis and discussion of the present case while completely objective may from the viewpoint of an interested party have appeared to be otherwise. This is often true where one litigant, feeling impelled to prevail over the other, places great emphasis on Ms own solution. A court in considering the problems of any disputants may choose either (a) the presented views which are to be finally adopted or (b) those supporting the opposing theory. The choice of one over the other is no reflection upon counsel, although it has apparently been so interpreted in this instance. Under the circumstances, we shall further delineate our views even though the petition for rehearing was not accompanied by a brief.1
As we interpret defendant’s petition, he insists that he does not comprehend the basis for our opinion, urging especially that:
(1) The burden is upon appellant to show wherein *194the trial court erred in its decision, all unspecified matters being waived.
(2) Defendant’s statement that plaintiff did not know of the bill of sale for the sheep until April 1, 1956, was borne out by the record.
(3) This court failed to give the reasons why the bill of sale covering the sheep was considered to be valid.
A review of the entire situation points up the reason for defendant’s continued insistence on the correctness of his position. It stems from his initial concept that the testimony of plaintiff’s daughter, Sharon Beck, was unworthy of belief and that “the court would have been at liberty to disregard it in its entirety.” As we pointed out in the original opinion, and shall discuss hereafter, we are in fundamental disagreement with defendant on this controlling point.
Adverting then to the first of the three points raised in the petition, we agree that the burden was on plaintiff (appellant) to show wherein the trial court erred in its decision and all unspecified matters were waived. However, plaintiff met the requirements of this rule by (a) alleging in the specifications of error that there was not competent evidence to support or warrant the findings of fact contained in the judgment and (b) in support thereof, presenting argument and legal authority that it was incumbent upon the court to consider the testimony of Sharon Beck.
In the opinion at 309 P.2d 717 we discussed a number of authorities relating to the necessity of a court’s considering uncontradicted testimony. Reference to that discussion is unwarranted here, except to note the *195impropriety of arbitrarily disregarding uncontradicted and unimpeached testimony. Since the judgment stated no reason for the disregarding of this witness’s unchallenged testimony, we assumed it to have been given consideration by the court. No other testimony was presented regarding either the delivery or the nondelivery of the bill of sale to plaintiff by the deceased. Thus, the finding of the court that the documents in question were never in fact actually delivered to plaintiff was clearly in error as unsupported by and contrary to the only testimony in the case.
Defendant’s second point, that plaintiff did not know of the bill of sale for the sheep until April 1, 1956, is closely related to the subject last above discussed. The testimony of the daughter clearly showed that plaintiff received the instrument on February 24, 1956, and consequently knew of it at that time; and plaintiff’s statement that she saw the writing on the bill of sale covering the sheep on April 1 was not a contradiction. Actually, the point is resolved by the well known rule that every witness is presumed to tell the truth, although such presumption is rebuttable and may be overcome. See 70 C.J. 760. 2 Bancroft's Code Practice and Remedies, 1927, p. 1888, states another version of the rule:
“* * * where the positive testimony of a witness is un-contradicted and he is unimpeached, — whether by other positive testimony or by circumstantial evidence, either intrinsic or extrinsic, — it cannot be disregarded, but should be considered by the jury. * * *”
This principle is supported by many cases and is sanctioned by all of the leading authorities. See Annotation, 8 A.L.R. 796; 6 Jones Commentaries on Evidence, 2d ed., p. 4887; and 9 Wigmore on Evidence, *1963d ed., p. 300 ff., which latter text cites two interesting cases: Chesapeake & O. R. Co. v. Martin, 283 U.S. 209, 51 S.Ct. 453, 75 L.Ed. 983; Jerke v. Delmont State Bank, 54 S.D. 446, 223 N.W. 585, 72 A.L.R. 7. In the present case, the daughter was not shown to have any interest in the outcome of the litigation, but even if this had been true, the testimony of a witness may not be disregarded merely because of an interest in the result. See In re Miller’s Will, 49 Or. 452, 90 P. 1002, 124 Am.St.Rep. 1051, 14 Ann.Cas. 277.
We turn then to defendant’s third point, that this court failed to give the reasons why the bill of sale covering the sheep was considered to be valid. This was not specifically discussed in the opinion. We did hold that the instrument by uncontroverted evidence was delivered to plaintiff (not to a third person) by the deceased and that no delivery of a tangible chattel is necessary to constitute a gift. By a fair inference, we held that there was no evidence of a gift causa mortis. We did not determine where the bill of sale was given in consideration of past services rendered unto deceased or was a gift. As the evidence was susceptible of either interpretation, we see no point in expressing any view on that subject.
The review occasioned by the petition serves to emphasize not only the initial obligation of a plaintiff to meet his burden of proof but also the succeeding obligation of a defendant to challenge plaintiff’s proof if he deems it to be vulnerable. In social or business life, it is sometimes possible to ignore or disregard the words of a speaker without reason; but in the orderly trial of cases, a litigant is entitled to assume that un-attacked evidence properly presented to a court will receive consideration and that the result of the action will depend upon the evidence which is adduced.
*197We find no sufficient reason for granting a rehearing and the same is therefore denied.
Numerous cases indicate that a party failing to so file is not entitled to consideration. See Tuttle v Rohrer, 23 Wyo. 305, 153 p. 27; Allen v. Houn, 30 Wyo. 186, 219 P. 573; and Henning v. Miller, 44 Wyo. 114, 14 P. 2d 437.