Real rage, unfortunately, is frequent. The body is carried erect or thrown forward, the limbs become stiff, mouth and teeth closely press together, the voice becomes very loud or dies away or grows hoarse, the forehead is wrinkled and the pupil of the eye contracted; in addition one should count the change of color, the flush or deep pallor. An opportunity to simulate real rage is rare, and anyway the characteristics are so significant that a mistake in recognition can hardly be made. Darwin says that the conviction of one’s own guilt is from time to time expressed through a sparkling of the eyes, and through an undefinable affectation. The last is well known to every penologist and explicable in general psychological terms. Whoever knows himself to be guiltless behaves according to his condition, naturally and without constraint: hence the notion that naïve people are such as represent matters as they are. They do not find anything suspicious in them because they do not know about suspicious matters. But persons who know themselves guilty and try not to show it, must attain their end through artifice and imitation, and when this is not well done the affectation is obvious. There is also something in the guilty sparkle of the eye. The sparkle in the eyes of beauty, the glance of joy, of enthusiasm, of rapture, is not so poetical as it seems, inasmuch as it is no more than intensified secretion of tears. The latter gets its increase through nervous excitation, so that the guilty sparkle should also be of the same nature. This may be considered as in some degree a flow of tears in its first stages.