Talkington v. Dumbleton is a United States Supreme Court case that was decided in 1887. The case involved a dispute between two parties over a contract for the sale of a horse. The plaintiff, Talkington, had agreed to purchase a horse from the defendant, Dumbleton, for $100. After the horse was delivered, Talkington refused to pay the full amount, claiming that the horse was not of the quality that had been promised. Dumbleton then sued Talkington for the full amount of the contract. The Supreme Court ruled in favor of Dumbleton, finding that Talkington had breached the contract by refusing to pay the full amount. The Court held that the contract was valid and enforceable, and that Talkington was liable for the full amount of the contract. The Court also held that the defendant was not required to prove that the horse was of the quality that had been promised, as this was a matter of fact that was to be determined by the jury. The Court's decision in Talkington v. Dumbleton established that a contract is valid and enforceable, and that a party who breaches a contract is liable for the full amount of the contract. The decision also established that a party is not required to prove the quality of goods or services that were promised in a contract.

Justice Field delivered the dissenting opinion in Talkington v. Dumbleton, arguing that the majority had failed to consider a key point of law. He argued that under California law, which was applicable to this case, an action for damages could not be brought against a party who had acted as an agent or trustee without first obtaining permission from their principal or beneficiary. In this case, it was undisputed that Dumbleton had been acting as an agent when he committed the acts complained of by Talkington and yet no such permission had been obtained prior to bringing suit against him. Therefore Justice Field concluded that there should have been judgment for Dumbleton on his demurrer and thus reversed the decision of the Supreme Court of California.