In this way the appeal to authority is both just, safe, and progressive. It is only a fool who will throw away all that the experience of the ages has built up. But the wisest man of all is surely he who, rejoicing in that great inheritance, can still appeal not to its outward form, but to its indwelling, living spirit, and carry forward the work which the past has done. The ages in the past that we value are not those in which people were mainly concerned to praise their predecessors, but those in which men were agreed to press forward to whatever new life God has in store. So it must be here: if we would be true to the great men of the past, to the authority of those who have built up our moral life, it will not be by standing still, but by moving on in the direction to which they point. The appeal to authority, then, will not be an appeal to practice, but always an appeal to principle; and so we shall be saved from that danger of moral experiment, a danger that is so immensely great because the individual who has made the experiment has thereby very often spoilt himself. One cannot experiment in the moral life with the detachment that we use in science. I may try mixing a couple of fluids together to see what happens, and I can regard the result quite accurately; but I cannot try the experiment of stealing, or of murder, in order to see what the real moral value of the thing is, because in the process of doing the act I shall vitiate my own soul; here the material in which we experiment is itself the instrument by which we have to judge; and the man who has once done an evil thing himself, very seldom has the same clearness of vision concerning its good and evil as the man who has kept true to some lofty purpose. The mere experiment, the mere trying what it feels like to be a murderer—not that anyone would take so extreme an instance as that—is always a method condemned in advance to futility, because in the process of making the experiment we destroy our power of judging the result. We want therefore to rely upon some authority; being unable to experiment for ourselves, we must follow the general rule that I have stated; the authority to which we appeal must be an authority of principle and not of practice. But what of the authority of our Lord Himself? To us who have accepted it, or who are trying to accept it, it is final; yet still, surely, in the spirit rather than in the letter. Why did He teach by a series of amazing paradoxes if it was not to prevent us setting up a code of rules as His legislation, if it was not to force us back upon the spirit of His teaching, behind the detailed regulations in which that spirit was embodied? Even here it is still true that the appeal is to the authority of His Spirit and not to that of detailed action or individual precept.