As the passions are agitations of the mind, and as most of them have an affinity to the impressions of the senses, they may be expressed by the movements of the body, and especially by those of the visage. Of what passes within we may form a judgment from the external motions of the body, and can know the actual situation of the soul by inspecting the changes of the countenance. But as the soul has no form which can have any relation to that of matter we cannot judge of it by the figure of the body, or by the features of the countenance. An ill-formed body may contain an amiable mind; nor is the good or bad disposition of a person to be determined by the features of the face, these features having no analogy with the nature of the soul on which any reasonable conjectures may be founded.
To this kind of prejudice, nevertheless, the ancients were strongly attached; and in all ages there have been men who have attempted to form into a science of divination their pretended skill in physiognomy; but it is evident that this divination can only extend to the situation of the mind when expressed by the motion of the eyes, visage, and other parts of the body, and that the form of the nose, the mouth, and other features, are no more connected with the natural disposition of the person, than is the largeness or the thickness of the limbs to that of thought. Shall a man have more genius because he has a better-shaped nose? Shall he have less wisdom because his eyes are little, and his mouth is large? It must be acknowledged, therefore, that the divination of physiognomists is without foundation, and that nothing can be more chimerical than their pretended observations.
Every object in Nature has its improvement and its decay. No sooner does the human form arrive at its limited perfection, than it begins to decline. The alteration is at first insensible, and even several years elapse before it becomes perceptible. Yet we ought to feel the weight of our years better than other people can estimate the number of them; and, as those are rarely deceived who judge of our age from external appearances, we would be still less so, as to the internal effect, if we did but observe ourselves more, and flatter ourselves less with false and idle hopes.