Arthur v. Zimmerman was a United States Supreme Court case that dealt with the issue of whether a contract between two parties was valid. The case involved a contract between Arthur and Zimmerman, in which Arthur agreed to pay Zimmerman a certain amount of money for the use of a certain piece of land. Arthur paid the money, but Zimmerman refused to give him the land. Arthur then sued Zimmerman for breach of contract. The Supreme Court held that the contract between Arthur and Zimmerman was valid and enforceable. The Court found that the contract was supported by consideration, meaning that both parties had given something of value in exchange for the other's promise. The Court also found that the contract was not against public policy, meaning that it did not violate any laws or regulations. The Court's decision in Arthur v. Zimmerman established that contracts between two parties are valid and enforceable, provided that they are supported by consideration and do not violate public policy. This decision has been cited in numerous other cases, and has become an important part of contract law in the United States.

Justice Field delivered the dissenting opinion in Arthur v. Zimmerman, arguing that the majority had misconstrued both state and federal law to reach their conclusion. He argued that under Missouri law, a contract was valid if it was made with consideration and did not violate public policy or any other legal provision; he further noted that no such violation existed here as there were no usury laws applicable to this case. Furthermore, Justice Field argued that even if the contract violated some sort of public policy, it should still be enforced because Congress had not passed any legislation prohibiting contracts like these from being enforced by federal courts. Finally, he asserted that since Congress has exclusive power over interstate commerce matters and could have prohibited such contracts but chose not to do so in this instance then they must be enforceable according to existing state laws governing them. In sum, Justice Field believed the majority's decision was wrongfully based on an incorrect interpretation of both state and federal law which would lead to unjust results for all parties involved in similar cases going forward unless overturned by higher authority