It is not so easy to consider fairly a question like this in the hour when vital personal interests pivot on the decision, as it is in a season of rest and safety; yet, if in a time of extremest peril the unvarying duty of truthfulness shines clearly through an atmosphere of sore temptation, that light may be accepted as diviner because of its very power to penetrate clouds and to dispel darkness. Being forced to consider, in an emergency, the possible justification of the so-called "lie of necessity," I was brought to a settlement of that question in my own mind, and have since been led to an honest endeavor to bring others to a like settlement of it. Hence this monograph. In the summer of 1863 I was a prisoner of war in Columbia, South Carolina. The Federal prisoners were confined in the common jail, under military guard, and with no parole binding them not to attempt an escape. They were subject to the ordinary laws of war. Their captors were responsible for their detention in imprisonment, and it was their duty to escape from captivity, and to return to the army of the government to which they owed allegiance, if they could do so by any right means. No obligations were on them toward their captors, save those which are binding at all times, even when a state of war suspends such social duties as are merely conventional. Only he who has been a prisoner of war in a Southern prison in midsummer, or in a Northern prison in the dead of winter, in time of active hostilities outside, can fully realize the heart-longings of a soldier prisoner to find release from his sufferings in confinement, and to be again at his post of duty at the front, or can understand how gladly such a man would find a way, consistent with the right, to escape, at any involved risk. But all can believe that plans of escape were in frequent discussion among the restless Federal prisoners in Columbia, of whom I was one. A plan proposed to me by a fellow-officer seemed to offer peculiar chances of success, and I gladly joined in it. But as its fuller details were considered, I found that a probable contingency would involve the telling of a lie to an enemy, or a failure of the whole plan. At this my moral sense recoiled; and I expressed my unwillingness to tell a lie, even to regain my personal liberty or to advantage my government by a return to its army. This opened an earnest discussion of the question whether there is such a thing as a "lie of necessity," or a justifiable lie. My friend was a pure-minded man of principle, ready to die for his convictions; and he looked at this question with a sincere desire to know the right, and to conform to it. He argued that a condition of war suspended ordinary social relations between the combatants, and that the obligation of truth-speaking was one of the duties thus suspended. I, on the other hand, felt that a lie was necessarily a sin against God, and therefore was never justifiable.