Plaintiff appeals from a summary judgment granted against bim on the ground that the cause of action he asserts had previously been used by him as an affirmative defense in an earlier action brought by one of the defendants.
*21Arthur Schuhardt sues defendants, Ernest and Erna Jensen, for $7,000 he allegedly loaned to them. They moved for summary judgment, stating that in a prior action Ernest Jensen had brought against plaintiff in the common pleas court for rent due, Schuhardt had successfully pleaded as a defense the cause of action he attempts to assert here. The circuit judge, in granting the motion for summary judgment, found that essential to the earlier judgment entered by the common pleas court in favor of Schuhardt was a determination of the issue he would raise here.
We concur that, under the circumstances found here, plaintiff should be estopped. When plaintiff raised his affirmative defense in the prior action, he chose to put in issue between the parties the same cause of action he would assert here. Under the interpretation of res judicata given for our jurisdiction by the Supreme Court in Ternes Steel Company v. Ladney (1961), 364 Mich 614, plaintiff is estopped.
Arthur Schuhardt is the brother of Erna Jensen. After the death of his wife, Shuhardt came to live with his sister and her husband until friction generated by his living in the defendants’ home caused him to leave. During the time he lived with the defendants, the plaintiff withdrew $7,000 from his bank account and gave that amount to the defendants who used the money to discharge the mortgage on their house. Now plaintiff claims that that $7,000 was a loan. The defendants claim it was a gift. The record before us provides no evidence, written or oral, to support the plaintiff’s bare assertion that these parties entered into a loan agreement.
But the crucial point here is that the issue has been litigated. Judge Stanczyk of the common pleas court for the city of Detroit, in the prior action brought by the defendant Ernest Jensen, gave judg*22ment for Schuhardt. Essential to the decision of the common pleas court was a finding that any obligation owed by Schuhardt was offset by the interest the Jensens allegedly owed him. This decision necessarily implies the finding that the loan existed. The plaintiff, having asserted his cause of action as an affirmative defense in the earlier suit, is estopped to assert it again here. Leslie v. Mollica (1926), 236 Mich 610; Ternes Steel Company v. Ladney, supra. In the prior action, plaintiff would have been entitled to counterclaim up to the $5,000 jurisdictional limit of the common pleas court, CLS 1961, § 728.1, as amended by PA 1965, No 392 (Stat Ann 1968 Cum Supp § 27.3651). Alternatively, since his claim was for more than the $5,000 jurisdictional limit then in effect, the plaintiff could have removed the action to the circuit court. CLS 1961, § 600.6935 (Stat Ann 1962 Eev § 27A.6935).
The plaintiff argues that he has not split his cause of action because, he claims, an action for the interest on a loan should be divisible from an action on the principal. But the plaintiff concludes this argument against himself because he concedes it is the law that an action for the principal and interest on a demand note is indivisible, and in his complaint in this action he explicitly claims that the disputed loan was due and owing on the date it was made. Shelton v. Wilson (1936), 274 Mich 433, relied upon by plaintiff, does not serve him; for there the Court, in concluding on the very different facts present there, recognized that in the case of a demand note only one claim can be brought. The claim, having-been used as an affirmative defense, cannot be sued upon in an independent action. Leslie v. Mollica, supra, and Ternes Steel Company v. Ladney, supra. All the cause of action plaintiff may have had on *23this disputed sum was merged in the judgment plaintiff had in the prior common pleas court action.
Affirmed. Costs to appellees.
J. H. G-illis and T. Gr. Kavanagh, JJ., concurred.