In the case of The Philadelphia and Reading Railroad Company v. Elias H. Derby, the Supreme Court was asked to decide whether a railroad company could be held liable for damages caused by an employee’s negligence while operating one of its trains. The plaintiff in error, the Philadelphia and Reading Railroad Company (P&R), argued that it should not be held responsible because it had no control over how its employees operated their trains or what they did on them. On the other hand, Elias H. Derby argued that P&R should have known about any potential risks associated with running a train and taken steps to prevent such accidents from occurring in the first place. After considering both sides’ arguments, the court ultimately ruled in favor of Derby and found P&R liable for his injuries due to their failure to exercise reasonable care when operating their trains. This decision established an important precedent regarding employer liability for negligent acts committed by employees during work hours or related activities; employers are now expected to take all necessary precautions against foreseeable risks posed by those under their supervision or employment agreement

In the dissenting opinion of The Philadelphia and Reading Railroad Company v. Elias H. Derby, Justice McLean argued that a contract between two parties should be enforced as written unless it is found to be illegal or against public policy. He disagreed with the majority's decision that an oral agreement made by one party could not supersede a prior written contract between them because he believed such agreements were valid under Pennsylvania law at the time. Furthermore, he asserted that if there was any ambiguity in interpreting either document then both documents should have been considered together to determine their meaning and effect on each other rather than relying solely on one over the other. In conclusion, Justice McLean felt strongly that contracts must be honored according to their terms regardless of whether they are verbal or written in order for justice to prevail and for society as a whole to benefit from contractual obligations being fulfilled without dispute or delay.