Until the scholars and the amateurs alike renounce their own presumption, their thrice stultified airs of finality, their estimate of their prejudice and their personal equation as a revelation from within, and their sacerdotal conviction that their science is the science of every case, they will have to be unkindly reminded that they are but blunderers like other men, that in their own specialties they convict each other of errors without number, and that the only path to truth is that of the eternal free play and clash of all manner of criticism. It is an exceptionally candid orthodox scholar who writes: "It is a law of the human mind that combating error is the best way to advance knowledge. They who have never joined in controversy have no firm grasp of truth. Hateful and unchristian as theological disputes are apt to become, they have this merit, that they open our eyes." [39] Let the conservative disputants then be content to put their theses and their arguments like other men, to meet argument with argument when they can, and to hold their peace when they have nothing better to add than boasts and declamation. Before the end of the nineteenth century the very school which we are asked to regard as endowed with quasi-papal powers in matters of historical criticism was declared by one of its leading representatives in Germany to have been on a wrong track for fifty years. In the words of Professor Blass:-- Professor Harnack, in his most recent publication, even while stating that now the tide has turned, and that theology, after having strayed in the darkness and led others into darkness (see Matt. xv, 14) for about fifty years, has now got a better insight into things, and has come to a truer appreciation of the real trustworthiness of tradition, still puts Mark's gospel between 65 and 70 A.D., Matthew's between 70 and 75, but Luke's much later, about 78-93. [40] And Blass, who dates Luke 56 or 60, goes on:-- Has that confessedly untrustworthy guide of laymen, scientific theology, after so many errors committed during fifty years, now of a sudden become a trustworthy one? Or have we good reason to mistrust it as much, or even more than we had before? In ordinary life no sane person would follow a guide who confessed to having grossly misled him during the whole former part of the journey. Evidently that guide was either utterly ignorant of the way, or he had some views and aims of his own, of which the traveller was unaware, and he cannot be assumed now to have acquired a full knowledge, or to have laid those views and aims wholly aside.