The first instructors of mankind were not very explicit in their "lessons to the million" as to the nature of these phantoms, but they could not help saying what they thought of them. One class, reflecting that these shadows melted into thin air and had no consistence, described them as immaterial or incorporeal, having shapes without matter, but coloured and defined. At the same time however, they denied that they were corporeal existences, or that they were coloured or figured; adding that they could clothe themselves with air as with a garment, when they wished to become visible to the eye of men. A second class assert that they were animated bodies, but that they were composed of air, or some still more subtle matter, which they could thicken at their pleasure, when they chose to make their appearance. § 2. If the two sorts of philosophers were opposed to each other in their opinion as to those shadows, they agreed as to their name, viz., Demons; in which respect they were as those who, when dreaming, believe that they see the souls of people departed, and that it is their own soul which they behold when they look into a mirror--or, in short, those who can believe that the reflections of the stars which they see in the water are the souls of the stars themselves. Out of this truly ridiculous belief they wandered into an era no less absurd; believing that these phantoms possessed unlimited power--an idea sufficiently devoid of reason, but current among the ignorant, who suppose that these beings, whom they know not, can exert a fearful influence. § 3. This most absurd creed was invented and promulgated by legislators, in order to support their own authority. They established this belief in spirits under the name of religion, hoping that the dread of these invisible powers which the people would entertain, might keep them to their duty. To give the more weight to their dogma, they classified those spirits or demons as good and bad; the one species being intended to stimulate men to the observance of their laws, and the other to act as a check and prevent their breaking them. To ascertain what these demons really were, it is only necessary to read the works of the Greek poets and historians, and above all, the Theogany of Hesiod, where he dwells at great length on the origin of the gods. § 4.