We must, however, declare that this primary fact is not irreducible, and that science ought not to be content to stop there, but should endeavour to explain and resolve it into its elements, so as to be able to say we have reached the point at which the genesis of myth really begins. This aim can only be attained by the decomposition by analysis of the primitive fact. Since intelligence in its essential elements, and in its innate and implicit exercise, appears to be the same in man and in animals, it is necessary to reduce the analysis of animal nature to a primary psychical fact, in order to see whether by this fact, which is identical also in man, the generating element of myth is really revealed. I propose to show that this research will reveal truths hitherto unattained, and explain the general law, not merely of the extrinsic process of science and of myth, but also of civilization. Starting from this wide basis, we must trace, step by step, the dawn, development, and gradual disappearance of myth. Since it is our business to consider science as well as myth, and their respective relations in the evolution common to both, we must, as briefly as possible in the present work, pause to consider these two factors of the human mind, observing the beginnings, conditions, and modes in which the one arose and gradually disappeared, while the other advanced and triumphed. We must not only regard the progress and transformation of religions, but also of science, as it is revealed in the philosophic systems of every age, in the partial or complete discoveries of genius, and in the great and stupendous achievements of modern experimental science. It would require a long treatise to fill so wide a field, which we must restrict to the limits of a few pages. Since our readers are now generally acquainted with the course pursued by human thought, and with the progress of peoples, but few landmarks or formulas are necessary to enable them to clear away obscurity and estimate facts at their just value, so as to understand what civilization and science have to do with the evolution of myth, and of science itself.