“Some colors are more agreeable than others, but these differ with different eyes, and with the nature of the color to which the eyes have been previously exposed. A bluish green relieves the eye when over-excited with red, and a mild red is agreeable after the protracted action of intense green; and in general, the complementary colors are most agreeable in succession. Again, it is well known, that no kind of light is painful, unless excessively vivid; we are pleased with a mild radiance in objects of every hue, from the whiteness of the moon to the crimson of the setting sun. But is there no other physical property by which these luminaries directly contribute to the gratification of taste? It is true that light, abstractedly from all objects is agreeable, and agreeable on the same principle that sweetness is to the taste, i. e., from the mere character of the nervous impression. But this is a pleasure merely passive, and in an active being it is, perhaps, on that account, one grade lower than the gratification afforded by the beauty of form, and is more allied to the gross pleasure of literal taste. Hence, we scarcely employ a figurative expression, in declaring that light is sweet. But the highest degree of physical gratification is not enjoyed by the eye, unless this agreeable excitant proceeds from an object of beautiful form. “Light is sweet,” but “it is a pleasant thing for the eyes to behold the sun.” What is the source of this additional pleasure which we receive, when light proceeds either by radiation or reflection from regular curvilinear objects?
“I shall offer what I believe to be an original and satisfactory explanation of the beauty of form, on principles purely physiological. It is based on the proposition, that the action of every muscle is attended with a sensation which, is at first agreeable, but which, if the action is continued for a short time with intensity, and without intermission, becomes painful. That there is pleasure attending those varied motions which depend upon the actions of different muscles in succession after intervals of rest in each, we know from our own consciousness as well as from that instinctive propensity to play which we observe in children and young animals. That the prolonged action of a muscle is painful, we may readily convince ourselves by endeavoring to hold the arm for some time at right angles with the erect trunk. With the arm in this position, a pound weight on the hand or even the weight of the arm itself becomes in a few minutes almost insupportable. We presently begin to feel pain in the shoulder and anterior part of the arm, the former from fatigue of those muscles which originate from the scapula and keep the os humeri elevated, and the latter from fatigue of the muscles which originate from the scapula and os humeri, whose muscular fibres are in front of the os humeri and by their contraction elevate the fore-arm in consequence of their tendinous attachment to its bones. Yet a man may labor all day with his arms without this painful sensation; because a muscle requires but a momentary rest, in order to regain that degree of energy which is momentarily lost by action.
“None but an anatomist can duly appreciate the variety of separate actions, on which depend the motions of a single limb, and the consequently numerous opportunities of rest which the muscles enjoy. To the superficial and unscientific observer, an arm is an arm; it is a single member which may be fatigued by a day’s work and recruited by a night’s rest. But to the anatomist the arm is a complex object, and its muscular energy is that of its component muscles, each of which may be fatigued by a minute’s action and recruited by a minute’s repose. It would be easy to extend this farther, and state reasons for believing that the component fasciculi and fibres of an individual muscle act still more transiently, and that their momentary and successive actions constitute the action of a single muscle.
“But waiving this refinement, it will be sufficient for our purpose to consider a single muscle as having a simple action, an action which cannot be sustained with uniformity a minute of time without actual pain, nor a second of time with positive pleasure. This, however, is not to be understood as an attempt to fix these limits with precision. To express the law in more general terms, as we diminish the duration of a muscle’s action we diminish the pain until we arrive at an action whose attendant sensation is neutral, i. e., neither painful nor pleasurable; as soon as we have passed that point and have begun to execute motions a little more transient, the attendant sensation becomes positively pleasurable, and the pleasure increases as the separate actions become more transient. It is not necessary to infer that there is attending each action of shorter duration a pleasure exceeding that which attends each action of greater duration; for the more transient actions are, in a given time, more numerous; so that with the same amount of pleasure for each muscular contraction, the amount of pleasurable sensation in a given time—say a second—would exceed the amount attending the less frequent and more prolonged actions in the same period: a greater number of separate impressions become—so to speak—crowded together and condensed, and thus produce a more vivid pleasure. Several contiguous impressions thus conspire to heighten the contemporaneous effect, inasmuch as we are unable to distinguish those impressions which are made at very short intervals on the muscular sense, any more than we are those made at very short intervals on the retina. We have an example of the latter in the familiar experiment of swinging a coal of fire in a circle, and in various optical instruments for combining colors and images.
“The proposition which I have endeavored to establish is, that there is a neutral point to which, if constant action is prolonged, its pleasurable character begins to be reversed; that the vividness of the sensation increases with the distance from this point, being on the one side pleasurable, on the other painful; the more transient the actions are, the more pleasurable; the more prolonged they are, the more painful.
“I am of opinion that this physiological principle is susceptible of interesting applications to a class of pleasures, which metaphysicians have regarded as exclusively mental, and dependant upon certain supposed ultimate principles of the constitution of mind, principles not resolvable into others more elementary. As physiology shall advance, it may be expected that many of these imaginary elements will yield to its searching analysis. Whether the writer has been so fortunate as to resolve any of the generally admitted elements of mental taste, the reader will be able to judge from the sequel.
As preparatory to the consideration of the beauty of form, it will be necessary to give an explanation of the gracefulness of motion. Although this has been vaguely and in part referred to ease of execution, yet, the physiological principle on which ease of execution depends, not having been clearly understood and distinctly stated, the gracefulness of all motions could not be referred to their true source. Thus, writers on taste have been under the necessity of admitting, as a distinct and independent source of gracefulness, the curvilinear direction of motions, and have been able to generalize this fact no farther than by referring it to the beauty of curved forms, which beauty was considered an ultimate fact. In applying the principles above developed, to the explanation of the pleasure or pain attending the contemplation of particular motions, we shall defer for the present the investigation of the intrinsic beauty of curved motions, which is the same as that of curved lines, and assume that in general those motions which are physically pleasurable to the agent are agreeable to the observer. The pleasure or pain of the agent will engage the sympathy of the observer; for he associates the observed action with his own experience. To make a single application, suppose a public speaker extend his arm horizontally and move it slowly in a horizontal position, through one third of a circle. This motion would not appear graceful. That it would not be performed with perfect ease, any one might prove by experiment. The principal difficulty is in preserving for a long time the horizontal position.”
“In the ordinary state of the muscular system, and within certain limits, the motion of the eye in any direction is pleasurable. Whenever the power of directing the eye is acquired, the tracing of a line will, to a certain extent and for a certain time, afford some degree of positive pleasure; in other words, any short line will possess some degree of positive beauty, and the infant becomes conscious of an emotion of which he was previously ignorant—the emotion of beauty of form. A point awakens no such emotion; it never will; it can possess no beauty. It must be recollected, that this has been restricted to minute points of inappreciable form. Circular dots will be considered under the head of figures. The colorific property of a dot as compared with that of the ground on which it is placed, may afford that kind of ocular pleasure which is foreign to the present inquiry.
“From points as compared with lines, we naturally proceed to lines as compared with each other.
“When the head is erect, in examining a straight horizontal line we employ one of the lateral recti; if the line be vertical we employ the rectus inferior or superior. In either case, but one muscle acts, and that continuously. The muscle is not relieved, and its action is not attended with the maximum amount of pleasurable sensation. When the vision has been extended along the whole line, if we then immediately proceed to examine it in the opposite direction, the opposite rectus must at one exert a force sufficient to overcome the momentum of the eyeball, and then exert a continuous action. Both these circumstances are unfavorable to pleasure. If the line is oblique, one lateral together with one inferior or one superior muscle is exerted, and the same principles which have been applied to the single muscles, apply to the muscles acting in pairs.