The simple and obvious truth is that there can be no field of human inquiry in which diversity of opinion can be avoided, for two reasons, that all knowledge possessed by us is incomplete, and active intelligence can not rest in the incomplete. Neither science nor theology can afford to dispense with hypothesis, that is conjecture, and where conjecture is, there is a wide region for devious wandering. Conjecture means inquiry into the unknown, and this is essential to intellectual life, equally necessary for science and religion, and accordingly diversity of opinion is inevitable in the history of both, as in the history of all forms of human activity. In every region of human knowledge there is a realm of the certain, and another of the uncertain, and accordingly there is diversity of opinion and conviction. Occasionally, in controversial writing, it is suggested that there is greater diversity of view in matters religious, than in matters scientific; and it is implied that such diversity is a reasonable ground of reproach. Both allegations are at fault, and the error arises from want of observation, involving imperfect acquaintance with the facts. Religion as it is concerned with the life of man himself, and is the subject of interest to all, has not only its common positions generally recognized, but also many of its phases of conflicting thought. Science, as it is beyond the range of the great majority as a subject of personal research, and within reach of only a limited number as a subject even of book knowledge, has its questions of conflict concealed to some extent from the public view. But, even moderate acquaintance with science makes us aware of the fact that there is conflict of opinion in every region of inquiry. Indeed it should be alien to the reflective observer, to marvel at the discovery of diversity of thought in any region, or to make its existence a ground for adverse criticism. Commonly accepted conclusions must afford the basis for competent criticism, whatever be the field of inquiry brought under review; diversity of opinion beyond and around these, must be accepted as the uniform attendant of human knowledge, indicating at once the provision for intellectual progress and the inducement to it. Thus, on grounds indisputable from a scientific basis, we escape the need for vindicating religion from the charge of having its claims to rational homage weakened, by the diversity of opinion found within the boundaries of religious thought. Such diversity is in strict accordance with familiar facts connected with every branch of science. Whatever may be said of the strong and paradoxical, because one-sided, utterance of Lessing,[A] it must be manifest that in all directions we are of necessity searchers after truth, and it is in such circumstances an intellectual weakness to object to the reliability of generally accepted conclusions, because they become starting-points for many lines of conflicting speculation.