Organs of sense, intellectual faculties, social affections, moral powers, are superadded endowments of a successively higher order: at the same time, they are the instruments of enjoyment of a nature progressively more and more exquisite. An organ of sense is an instrument composed of a peculiar arrangement of organized matter, by which it is adapted to receive from specific agents definite impressions. Between the agent that produces and the organ that receives the impression, the adaptation is such, that the result of their mutual action is, in the first place, the production of sensation, and, in the second place, the production of pleasure. The pleasure is as much the result as the sensation. This is true of the eye in seeing, the ear in hearing, the hand in touching, the organ of smell in smelling, and the tongue in tasting. Pleasure is linked with the sense; but there might have been the sense without the pleasure. A slight difference in the construction of the organ, or in the intensity of the agent, would not merely have changed, it would even have reversed the result; would have rendered the habitual condition of the eye, the ear, the skin, not such as it now is in health, but such as it is in the state of inflammation. But the adjustment is such as habitually to secure that condition of the system in which every action that excites sensation produces pleasure as its ordinary concomitant; and the amount of enjoyment which is thus secured to every man, and which every man without exception actually experiences in the ordinary course of an ordinary life, it would be beyond his power to estimate were he always sensible of the boon; but the calculation is altogether impossible, when, as is generally the case, he merely enjoys without ever thinking of the provisions which enable him to do so. But if the pleasures that arise from the ordinary operations of sense form, in the aggregate, an incalculable sum, how great is the accession brought to this stock by the endowments next in order in the ascending scale, namely, the intellectual faculties!