Thus conceived, the course of evolution is comparable, not as before, to the gradual unveiling of a blank canvas, revealing simply a greater extent of the same appearance, but to the gradual unveiling of a picture whose full unity of meaning is held in suspense till the disclosure is completed. We do not now interpret the higher by the lower, but the lower by the higher; the beginning by the end. This may seem perilously near to finalism, yet it is no more necessarily so, than the process of photography; we only need a self-adaptive tendency in life-matter responsive to the stimulating-tendency of the environment. Not, of course, that this bundle of words really explains anything, but that like other formulae of the kind, it prescinds from the question of ends and origins, by making a statement of what happens serve as a cause of what happens, and calling it a Law or a Tendency, or a Latent Potentiality--thus filling the gap which mere agnosticism creates in our thought. With this conception of Evolution our ordinary estimates of "higher" and "lower" are saved; also the value of our mental processes upon which rests whatever proof the theory may admit of; while the "argument from adaptability" is provided with a firm basis independent of finality. All our "natural," as opposed to our personal and self-determined appetites or cravings,--those which are, so to say, constitutional and inseparable from our nature in certain conditions, are evidence of the influence of some reality outside us seeking to draw us into more perfect correspondence with itself, and whose nature can be more or less dimly conjectured from the nature of those cravings. What are called "natural religions" represent man's self-devised attempts to explain the reality answering to his religious and moral cravings. Revelation is but a divine interpretation of the same; as though one with dim vision were to supplement his defect by the testimony of another more clear-sighted.