Aron v. Manhattan Railway Company was a Supreme Court case that was decided in 1895. The case involved a dispute between a passenger and a railway company over the payment of a fare. The passenger, Aron, had purchased a ticket from the railway company, but the company refused to accept it and demanded that he pay an additional fare. Aron refused to pay the additional fare and sued the railway company for breach of contract. The Supreme Court held that the railway company was liable for breach of contract. The Court found that the railway company had failed to honor the terms of the contract by refusing to accept the ticket that Aron had purchased. The Court also held that the railway company was liable for damages, as Aron had been deprived of the benefit of his bargain. The decision in Aron v. Manhattan Railway Company established that a railway company is liable for breach of contract when it fails to honor the terms of a contract with a passenger. The decision also established that a railway company is liable for damages when a passenger is deprived of the benefit of his bargain.

In the case of Aron v. Manhattan Railway Company, Justice Harlan delivered a dissenting opinion in which he argued that the majority's decision was wrongfully based on an interpretation of New York law and not on federal common law. He believed that it should have been determined by looking at whether or not there had been any negligence committed by either party involved in this dispute over a railway accident. According to him, if there had been no negligence then neither party would be liable for damages caused by the incident; however, since both parties were found to be negligent they should both bear responsibility for their actions and thus share liability accordingly. Furthermore, he also noted that even though one party may have acted more negligently than another does not necessarily mean they are solely responsible for all damages incurred as a result of their actions - instead each must take responsibility according to how much fault can be attributed to them individually. Ultimately, Justice Harlan concluded his dissent with an argument against allowing state laws to dictate decisions made under federal common law when determining matters such as these involving interstate commerce disputes between two different states’ citizens or companies