This duty, which is a duty of charity for men in general, is a duty of justice for the physician and all those who have care of the sick. The physician owes his devotion to the patient, as the soldier owes his to his country. In both these cases _medical duty_, _military duty_, devotion is a strict duty. It is at the same time a duty towards men and a duty towards the profession. It is in both cases what may be called the _honor of the flag_. Thus do we every year see a certain number of young hospital physicians die, like soldiers on the field of honor. The duty of attending the sick and being thereby exposed to contagion, falls alike on all who have chosen this profession: sisters of charity, the nurses, the male and female attendants in infirmaries. It is also a duty in the family; the parents owe themselves to their children; the servants themselves should assume in a certain measure the same responsibility, although it is the duty of the masters to spare them as much as possible. Moreover, it is known how common this devotion is, especially with mothers, and how many of them die of the illness they have contracted at the bedside of their children. In all these circumstances, it is of course not forbidden to be cautious, and wisdom requires one should not go beyond the strictly necessary; but the necessary is obligatory; and on whom should it fall more naturally than on the parents? Besides the illnesses which threaten the lives of men, there are dangers more sudden, more violent, more terrible, which arise from the invasion of the forces of nature: fire and water are the most terrible; conflagrations, inundations, shipwrecks, catastrophes of all kinds imperil the lives of men. Here the question is no longer one of slow and leisurely attentions. To save a life which a minute later will be extinguished, there is wanted a sudden resolution, a well-tested courage, and the will to risk one's life for that of another. In these terrible circumstances there are some men who seem to be more naturally called than others to sacrifice themselves; for example, firemen and sailors. It is certain that it is those who are the more familiar with the element it is necessary to combat, that are most called to do so, and for whom self-devotion becomes a greater duty. But it is not always possible to have them immediately at hand; in a sudden catastrophe, all must take their share of the peril; all must be ready to give their life for others if they can do so with some utility.