First in order, both from necessity and because of its importance, is the principle of faith. And following the same method of investigation I adopted at the commencement of this inquiry, _viz_: defining as clearly as I am able, the meaning of the words and terms used, I come to the question. What is faith? And in answer say that it is an assurance in the mind of the existence and reality of things which one has not seen, or which to him have not been demonstrated. It may be an assurance in the mind of the existence of some Being whom we have not seen, but whose works are visible, and who has been seen by others; or it may be of the transpiring of some event at which we were not present, but of which others bear witness; or it may be an assurance of the correctness of certain deductions based upon scientific calculations, though the principles of the science, and the method of dealing with them, by which the conclusions are reached, we neither understand nor are able to follow; in whatever it may be, that assurance of the mind which accepts as truth those things which one has not seen, and does not know for a certainty from his own experience to be absolutely true, is faith. For example, to bring to our aid the assistance of illustration, few, perhaps none of my readers have ever seen the Lord Jesus Christ; yet the writers of the New Testament bear testimony to the reality of his existence, and relate the circumstances which make up his eventful career. The writers of the Book of Mormon do the same in relation to his labors on the western hemisphere Joseph Smith testifies that, in vision, he saw both Jesus and his Father, in the spring of 1820.[A] Joseph Smith and Sidney Rigdon bear record that they saw him in February, 1832;[B] and Oliver Cowdery and Joseph Smith say they saw him in the Kirtland Temple, in April, 1836.[C] These evidences establish an assurance, or faith, in the mind, concerning the existence of Jesus, the Lord. [Footnote A: Pearl of Great Price, p. 59.] [Footnote B: Doc. and Cov., sec. 76.] [Footnote C: Doc. and Cov., sec. 110.] Again, none of us, and perhaps no one living, was at the battle of Waterloo; yet the fact of that battle taking place is testified to by many historians; no one doubts it, and the evidence in the case is so certain, that one may say he has perfect faith or assurance, approaching almost within the lines of absolute knowledge, that the event transpired--that assurance in the mind is faith.