The first is to take them in the order of Intellectual development. Some of the senses are evidently intellectual in a high degree, as Sight and Hearing, others are intellectual in a much smaller degree, as Smell and Taste. The organic sensations are still less connected with the operations of the intellect. Many of the least intellectual sensations are remarkably intense, as pleasure and pain; perhaps more so than the intellectually higher class. The organic pains are more unendurable than the worst pains of hearing or of sight, unless these are assimilated to the other class, by injury of the organs. The intellectual superiority of the higher senses shows itself in two ways, the one strictly in the domain of Intellect, the other in the domain of Feeling. As regards Intellect, it is shown in the predominance of the ideas of the higher senses. Our intellectual or ideal trains, the materials of thought and knowledge, are made up most of all of ideas of sight, next of ideas of hearing, to a less degree of ideas of touch or skin contact, and, least of all, of ideas of stomach and lung sensations or other organic states. The trains of the scientific man, of the man of business, and even of the handicraft worker, are almost entirely made up of ideas of sight and of hearing (with active or muscular ideas). Our understanding of the order of nature, our very notion of the material universe, is a vast and complex scheme of ideas of sight. The intellectual superiority of the higher senses in the domain of Feeling is connected with the remembrance or ideal persistence of pleasures and pains. The pleasures of Digestion are weakly and ineffectively remembered, in the absence of the actuality. The pleasures of Smell are remembered better. The pleasures and pains of Hearing and Sight are remembered best of any. This gives them a higher value in life; the addition made to the actual, by the ideal, is, in their case, the greatest of all. They are said, for this among other reasons, to be more refined. The arrangement dictated by the gradation of intellectuality would be as follows:--1. Sensations of Organic Life. 2. Taste. 3. Smell. 4. Touch. 5. Hearing. 6. Sight. The second principle of arrangement starts with Touch, as the most simple in its mode of action, and the most diffused in its operation. Touch consists in mere mechanical pressure on a sensitive surface; this is the most simple and elementary of all stimuli. The other senses are regarded as specialised modifications of Touch.