The doctrine of res judicata is based upon the primary right theory. (Crowley v. Katleman (1994) 8 Cal.4th 666.) In Crowley v. Katleman (1994) 8 Cal.4th 666, the California Supreme Court explained: "The primary right theory . . . provides that a 'cause of action' is comprised of a 'primary right' of the plaintiff, a corresponding 'primary duty' of the defendant, and a wrongful act by the defendant constituting a breach of that duty. The most salient characteristic of a primary right is that it is indivisible: the violation of a single primary right gives rise to but a single cause of action. A pleading that states the violation of one primary right in two causes of action contravenes the rule against 'splitting' a cause of action. As far as its content is concerned, the primary right is simply the plaintiff's right to be free from the particular injury suffered. It must therefore be distinguished from the legal theory on which liability for that injury is premised: 'Even where there are multiple legal theories upon which recovery might be predicated, one injury gives rise to only one claim for relief.' The primary right must also be distinguished from the remedy sought: 'The violation of one primary right constitutes a single cause of action, though it may entitle the injured party to many forms of relief, and the relief is not to be confounded with the cause of action, one not being determinative of the other.' " (Id. at pp. 681-682.)