What has been said with regard to a revelation, made by words, applies, in its main points, to a revelation made directly to the mind through _ideas_, without the intervention of words. To see this clearly, let us bear in mind the distinction between a perception and an idea. An idea is the result of a perception. We perceive a rose when it is presented to our senses, and we see, smell, or touch it. We have an idea of it, when, not being any longer presented, we think of it, and call to mind its qualities. We are said to have a perception of anger, or love, or any other emotion, when those feelings are present to the mind. We have ideas of them, when we think about them. It is not our object to enter upon any abstruse discussion as to the origin of ideas. What has been just advanced will be generally admitted by metaphysicians, and readily understood by others. Hoping, then, that the distinction between an idea and a perception will be carried in the mind, we will proceed with our argument. There is no difficulty in supposing—and this, we believe, corresponds very closely to an opinion commonly entertained respecting inspiration—that God could, without the intervention of words, call up in the mind such ideas as He might think fit. For instance, instead of speaking the words, “Thou shalt do no murder,” He might, in a preternatural manner, excite in the mind the ideas corresponding to them. Still, however, unless we suppose the conditions of human thought to be altered in a manner for which we have no analogy, the ideas of a man, killing, etc., must previously exist in the mind, or the revelation would be unintelligible. Whether, then, the ideas are called up, through the instrumentality of words, or in some other way, is immaterial to our present argument. The point we insist on is that, except in the case of actual perception, the communication of knowledge, by revelation, or otherwise, _must be limited by the ideas previously existing in the mind of the person to whom the communication is made_. These ideas may be combined into new forms, and new relations may be discovered between them, or they may be analyzed into their constituent parts, but we cannot transcend the ideas themselves, except by new perceptions.