As for the How and Why of need for the moving power, it is that whereas the position of the animal is not the same as the position of the plant in its adaptation for attracting such foods as are useful and pushing off such as are harmful and incompatible, but on the contrary as this is brought about for the animal through a sort of earning by self-help, it needs a moving power for the purpose of drawing to itself the useful and driving away the harmful. Wherefore all the powers of the animal are either perceiving or motion-promoting. The motion-promoting is the yearning (desiderative, longing, craving) power: it is either urging on to the search after a chosen object of animal good, and then it is the lusting power; or else it is urging on to the warding off of an object of animal dislike, and then it is the hating power (angry power). The perceiving power too is either outward (apparent), such as the five senses; or else inward (internal, hidden), such as the picturing, the imaginative, the conjecturing, and the remembering power. Furthermore, the motion-promoting power does not cause to move save on a peremptory bidding from the conjecturing, through the agency (means) [or by the employment] of the imaginative. Also, the motion-promoting power, in animals other than the speaking (or rational) species, is the aim and end; and this is so, because the motion-causing power is not imparted unto them in order that they shall through it direct aright the workings of sensation and imagination so as to adapt these workings to the attainment of their own good, but on the contrary the power of sensation and of imagination are imparted to the non-speaking irrational animals solely in order to direct aright through them the workings of motion, and to adapt these workings to the good of the animals. Whereas, the speaking rational species of living beings is on the reverse wise; because unto it was imparted the motion-causing power wholly and solely in order that through this power it shall be fitted to set aright the speaking self, i.e., the rational intelligent soul, not the other way about. Thus then, the motion-promoting power in the irrational animal is, as it were, the prince commander that is served; the five senses, the spies that are sent forth; the perceptive power, the post-master of the prince commander unto whom the spies return; the imagining power, the foot-messenger going to and fro between the post[H][12] and the post-master; the conjecturing power, the prince’s adjutant minister; the remembering power, the closet of state papers. As for the starry firmament and plants, the feeling power and the imagining power have not been imparted unto them, even though each one of them has a soul and though it has life: the firmament has not these powers, because of its loftiness; plants have them not, because of their abasement in comparison to it. FOOTNOTES: [H] or wazir, minister.