When a well broken horse, for example, goes on his way quietly, perceiving nothing which strongly attracts nor alarms him, the sudden flutter of a cloth, the flaring of a lamp, the rush of water, or some violent noise will cause him to stop, to plunge and kick, or to bolt away.  We have already shown, by experiment, the exciting cause of his alarm and suspicion.  The sudden fluttering of the cloth in the wind was a phenomenon perceived by the horse, and since he regarded this phenomenon as an animated subject, and consequently as a real power, it is evident that his fear was caused by the sudden appearance of a living form, and the direct apprehension of a subject which might possibly be hurtful or dangerous.  In this way, the circle is completed and combined in one unique phantasm; a phenomenon, a living subject, and a real power.

In this instance, the psychical law is so clear that it can hardly be disputed.  But if we consider any other animal perceptions, we find that the law still holds good, as we have already shown in various instances.  In all cases the apprehension takes place in the same way, and consists of the same elements, namely, of a phenomenon, a living subject, and a real power.  The exercise of animal apprehension is the rapid, necessary, and perpetual concentration into a single image of the phenomenon, subject, and cause; that is, given the perception of a phenomenon, the animal endows it, with respect to himself, with consciousness, and consequently with real power.

In fact, the faculty of perception cannot be exercised in any other way, nor can it consist of any other elements.  In nature, the sensible qualities of things are all resolved into general and special phenomena, appearances, and extrinsic forms, as far as animal and human intuition, and the character of the subject which perceives and feels them, are concerned; and they are perceived just so far as we and as animals are able to communicate by means of our senses with the world and with ourselves.  A phenomenon and an intrinsic form signify, at the moment of perception, the thing, the object which the conditions of our senses enable us to perceive, and the intrinsic power of this phenomenon implies a cause.  Natural phenomena and beings are thus reciprocally linked together as causes and effects, an effect becoming in its turn the cause of a subsequent fact; that is, when we consider things in themselves, and not relatively to the animal or man who apprehends them.

If, therefore, there are in animal consciousness and intelligence three elements of apprehension, afterwards fused into a single fact, it follows that the extrinsic relations of beings and forces are subjectively reciprocal; there is the given form of a phenomenon, and, intrinsically, it consists of an active power, eternally at work, since there is no being nor form which stands still and is not reproduced in the infinite evolution of the universe.