Conscience may develop, without losing entirely its instinctive or impulsive character, to practical reason. This takes place through the development of the conceptions which determine the conscience as impulse, to greater clearness and distinctness. When conscience acts as instinct, the individual does not know what he does. If it acts as impulse, he has a dawning consciousness of his acts. And when it becomes practical reason, there arises a clear consciousness of ethical laws and ethical ideals. In different individuals, conscience may appear in very different forms and degrees, as instinct, impulse, practical reason, sense of duty, sense of justice. Sometimes it appears as mainly negative and restraining, sometimes again as chiefly positive, partly harmonizing and partly increasing. Here it appears as enthusiastic devotion, there as quiet and continuous tendency. It would be impossible to name even the principal forms in which it may manifest itself, but it is of great importance to call attention to the fact of these individual differences, since we suffer at present from a dogmatism that has but one measure for all these different manifestations. We must go a step farther still. There may be men who possess no strictly ethical feeling and who do not need it. Such men do what they can with their whole heart without applying any reflective standard to their own or others' acts. They entirely absorb themselves with unflagging zeal in a work that perfectly corresponds to their capabilities and impulses, without any doubt of its rightfulness and import. They may devote themselves to art and science, to the service of society, or to their family. Or they belong to the class of happy natures who spread light and joy by their mere existence. They act in accordance with the law, without being in possession of the law, and what objection can Ethics have to offer to this? Ethics is for the sake of life, not life for the sake of Ethics. Since all ethical judgments have conscience for their psychological basis, conscience is highest authority, highest law-giver, in comparison with which every other authority is subordinate and derived. To wish to go beyond one's conscience is to wish to go beyond oneself. When I yield to another human being whose judgment I trust more than my own, this can be justified only as it takes place through my conscience. Conscience is infallible, if one understands by infallibility that it is, at every instant, the highest judge; this infallibility does not mean, however, that it does not err. Every earnest conviction takes the form of conscience; the truth is not, however, secured by the mere form. Was it not from conviction that Aristotle asserted the right of slavery, and Calvin, with Melancthon's approval, sent Servetus to the stake?