"It (theology) is the science of all other sciences and useful arts, being in fact the very foundation from which they emanate. It includes philosophy, astronomy, history, mathematics, geography, languages, the science of letters, and blends the knowledge of all matters of fact, in every branch of art and research.......All that is useful, great and good, all that is calculated to sustain, comfort, instruct, edify, purify, refine or exalt intelligences, originated by this science, and this science alone, all other sciences being but branches growing out of this, the root."--Pratt, Key to Theology, chap. 1.] [Sidenote: Man must not expect direct revelation in matters that he can solve for himself.] It is not in harmony with the Gospel spirit that God, except in special cases, should reveal things that man by the aid of his natural powers may gain for himself. The Lord spoke to the Prophet as follows:--"Behold, you have not understood; you have supposed that I would give it unto you, when you took no thought, save it was to ask me; but, behold, I say unto you, that you must study it out in your mind; then you must ask me if it be right, and if it is right I will cause that your bosom shall burn within you; therefore, you shall feel that it is right."[A] Such a doctrine makes it unreasonable to look to the Prophet's work for a gratuitous mass of scientific or other details, which will relieve man of the labor of searching out for himself nature's laws. So well established is this principle that in all probability many of the deepest truths contained in the writings of Joseph Smith will not be clearly understood, even by his followers, until, by the laborious methods of mortality, the same truths are established. It is even so with the principles to be discussed in the following papers. They were stated seventy years ago, yet it is only recently that the Latter-day Saints have begun to realize that they are identical with recently developed scientific truths; and the world of science is not yet aware of it. However, whenever such harmony is observed, it testifies of the divine inspiration of the humble, unlearned boy prophet of the nineteenth century. [Footnote A: Doctrine and Covenants 9:7, 8.] [Sidenote: The absence of the language, details and methods of science in the Prophet's writings proves him unfamiliar with the written science of his day.]