In Zeller et al. v. Switzer, the Supreme Court of the United States was asked to decide whether a contract between two parties was valid and enforceable. The contract in question was between Zeller and Switzer, and it stated that Switzer would pay Zeller a certain amount of money in exchange for Zeller's promise to convey certain real estate to Switzer. The Supreme Court held that the contract was valid and enforceable. The Court reasoned that the contract was supported by consideration, which is an essential element of a valid contract. The Court noted that the consideration was the promise of Zeller to convey the real estate to Switzer, and that this promise was sufficient to support the contract. The Court also held that the contract was not void for lack of consideration. The Court noted that the consideration was sufficient to support the contract, and that the consideration was not illusory or uncertain. The Court also noted that the consideration was not illegal or against public policy. In conclusion, the Supreme Court held that the contract between Zeller and Switzer was valid and enforceable. The Court reasoned that the contract was supported by consideration, and that the consideration was not illusory, uncertain, illegal, or against public policy.

Justice Field delivered the dissenting opinion in Zeller et al. v. Switzer, arguing that the majority had misapplied a prior Supreme Court decision and misinterpreted an Illinois statute to reach its conclusion. He argued that under the terms of the contract between Zeller and Switzer, it was clear that they intended for interest to accrue on any unpaid balance after maturity until payment was made in full; this intention should have been respected by both parties as well as by courts of law. Furthermore, he noted that while there may be some ambiguity regarding whether or not interest could be collected from a debtor who has already paid off their debt but is still awaiting reimbursement from their creditor, such ambiguities should always be resolved in favor of protecting creditors’ rights rather than those of debtors since creditors are more likely to suffer losses due to delays caused by legal proceedings or other factors beyond their control. In sum, Justice Field concluded his dissent with a reminder that contracts must always be interpreted according to what both parties reasonably believed them to mean at the time they were entered into and not based on subsequent judicial interpretations which may differ significantly from what either party originally intended when signing said agreement