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is complex enough almost to baffle our efforts at analysis. But it is not to be compared with the intricate differentia tion of functions in the animal body. The latter s elab orate apparatus of bony and muscular structure, of nutri tive and circulatory functions and of specialized senses, all interrelated in a maze of simple and compound reflex ner vous circuits, forms a microcosm which excites the amaze ment of every intelligent student. But one is lost in won der when he penetrates beyond the physiological organ ization into the biological realm and begins to consider the microscopical constitution and organization of the highly specialized cells of which these several organs are composed. The body of man duplicates the essential functions of the animal organism, while in the human brain it comes to be a veritable marvel of unity in complexity, wherein the reflex and instinctive nervous organization of the animal, suitably modified, is crowned with a dome of grey matter, the subtile intricacy and delicacy of whose organization constitutes the miracle of the material universe. It is a material instru ment which places at the disposal of man a vast range and variety of possible reactions upon his environment. In some mysterious way it is intimately related to conscious ness, using the word in its narrower and more usual mean ing; and in an equally mysterious way it seems closely con nected with that capacity in which man so far excels all lower creatures the power to retain and revive past in dividual experiences.
This leads me to observe that corresponding to this rising scale of organic complexity there is a parallel psychical de velopment. We are at a loss to characterize the mode of life of the vegetable kingdom ; but we are safe in assuming that, properly speaking, it is not a psychical life. There is nothing in the plant corresponding to consciousness in the ordinary sense of that word. Those who take con sciousness to be a universal quality or mode of life, must, of course, make it co-extensive with life ; and must, there fore, maintain that there is a vegetable consciousness. But
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