However, in order to understand these facts and their interpretations, it is necessary to pass in review the fundamental characteristics of living beings. It will be shown that these very characteristics are found in inanimate matter. CHAPTER I. UNIVERSAL LIFE. OPINIONS OF PHILOSOPHERS AND POETS. § 1. Primitive beliefs; the ideas of poets.—§ 2. Opinions of philosophers—Transition from brute to living bodies—The principle of continuity: continuity by transition: continuity by summation—Ideas of philosophers as to sensibility and consciousness in brute bodies—The general principle of homogeneity—The principle of continuity as a consequence of the principle of homogeneity. § 1. PRIMITIVE BELIEFS. IDEAS OF THE POETS. The teaching of science as to the analogies between brute bodies and living bodies accords with the conceptions of the philosophers and the fancies of the poets. The ancients held that all bodies in nature were the constituent parts of a universal organism, the macrocosm, which they compared to the human microcosm. They attributed to it a principle of action, the _psyche_, analogous to the vital principle, and this psyche directed phenomena; and also an intelligent principle, the _nous_, analogous to the soul, and the _nous_ served for the comprehension of phenomena. This universal life and this universal soul played an important part in their metaphysical systems. It was the same with the poets. Their tendency has always been to attribute life to Nature, so as to bring her into harmony with our thoughts and feelings. They seek to discover the life or soul hidden in the background of things. “Hark to the voices. Nothing is silent. Winds, waves, and flames, trees, reeds, and rocks All live; all are instinct with soul.” After making proper allowance for emotional exaggeration, ought we to consider these ideas as the prophetic divination of a truth which science is only just beginning to dimly perceive? By no means. As Renan has said, this universal animism, instead of being a product of refined reflection, is merely a legacy from the most primitive of mental processes, a residue of conceptions belonging to the childhood of humanity. It recalls the time when men conceived of external things only in terms of themselves; when they pictured each object of nature as a living being. Thus, they personified the sky, the earth, the sea, the mountains, the rivers, the fountains, and the fields. They likened to animate voices the murmur of the forest:— “ ... The oak chides and the birch Is whispering.... And the beech murmurs.... The willow’s shiver, soft and faint, sounds like a word. The pine-tree utters mysterious moans.”