HAECKEL'S BELIEF IN THE OMNIPOTENCE OF MATTER 199 



but no nerves or specific organs of sense. The nerve-soul (neuropsyche) ; the psychic life of all the higher animals 

 is conducted, as in man, by means of a more or less complicated ' psychic apparatus.' This apparatus is always 

 composed of three chief sections : the organs of sense are responsible for various sensations ; the muscles effect the 

 movements ; the nerves form the connection between the two by means of a special central organ, the brain or 

 ganglion. The gangUonic cells, or ' psychic-cells,' which compose the central nervous organ, are the most perfect 

 of all organic elements ; they not only conduct the commerce between the muscles and the organs of sense, but 

 they also effect the highest performances of the animal soul, the formation of ideas and thoughts, and especially 

 consciousness. The long ancestral history of our ' vertebrate-soul ' commences with the formation of the most 

 rudimentary spinal cord in the earliest acrania ; slowly and gradually, through a period of many millions of years, 

 it conducts to that marvellous structure of the human brain which seems to entitle the highest primate form to 

 quite an exceptional position in nature. No phenomenon of the life of the soul is so wonderful and so variously 

 interpreted as consciousness. Consciousness is a vital property of every cell. It is found in all organisms, animal 

 or vegetal, but not in lifeless bodies (such as crystals). This opinion is usually associated with the idea that all 

 organisms (as distinguished from inorganic substances) have souls : the three ideas — life, soul, and consciousness — 

 are then taken to be co-extensive. Fechner has endeavoured to prove that the plant has a ' soul,' in the same 

 sense as an animal is said to have one ; and many credit the vegetal soul with a consciousness similar to that of 

 the animal soul. In truth, the remarkable stimulated movements of the leaves of the sensitive plants (the mimosa, 

 drosera, and dionaea), the automatic movements of other plants (the clover and wood-sorrel, and especially the 

 Hedysarum), the movements of the ' sleeping plants ' (particularly the papilioncwea), &c., are strikingly similar to 

 the movements of the lower animal forms : whoever ascribes consciousness to the latter cannot refuse it to such 

 vegetal forms. The peculiar phenomenon of consciousness is not, as du Bois-Raymond and the dualistic school 

 would have us believe, a completely ' transcendental ' problem ; it is, as I (Haeckel) showed thirty-three years ago, 

 a physiological problem, and, as such, must be reduced to the phenomena of physics and chemistry. The con- 

 ception of the soul as a ' substance ' is far from clear to many psychologists ; sometimes it is regarded as an 

 ' immaterial ' entity of a peculiar character in an abstract and idealistic sense, sometimes in a concrete and reahstic 

 sense, and sometimes as a confused tertium quid between the two. If we adhere to the monistic idea of substance, 

 we find energy and matter inseparably associated in it. We must distinguish in the ' substance of the soul ! ' the 

 characteristic psychic energy which is all we perceive (sensation, perception, volition, &c.), and the psychic matter, 

 which is the indispensable basis of its activity — that is, the living protoplasm. Thus, in the higher animals the 

 ' matter ' of the soul is a part of the nervous system ; in the lower nerveless animals and plants it is a part of the 

 multicellular protoplasmic body ; and in the unicellular protists it is a part of their protoplasmic cell-body. The 

 supreme and aU-pervading law of nature, the true and only cosmological law, is, in my opinion (Haeckel), the law 

 of substance ; all other known laws of nature are subordinate to it. Under the name of ' law of substance ' we 

 embrace two supreme laws of different origin and age — the older is the chemical law of the ' conservation of matter,' 

 and the younger is the physical law of the ' conservation of energy.' Among the various modifications which the 

 fundamental idea of substance has undergone in modern physics, in association with the prevalent atomism, we 

 shall select only two of the most divergent theories for a brief discussion, the kinetic and the pyknotic. Both 

 theories agree that we have succeeded in reducing all the different forces of nature to one common original force ; 

 gravity and chemical action, electricity and magnetism, light and heat, &c., are only different manifestations, 

 forms, or dynamodes, of a single primitive force (prodynamis). This fundamental force is generally conceived as 

 a vibratory motion of the smallest particles of matter— a vibration of atoms. The atoms themselves, according 

 to the usual ' kinetic theory of substance,' are dead, separate particles of matter, which dance to and fro in empty 

 space and act at a distance. The real founder and most distinguished representative of the kinetic theory is 

 Newton, the famous discoverer of the law of gravitation. In his great work, the Philosophiae Naturalis Principia 

 Mathematica (1687), he showed that throughout the universe the same law of attraction controls the unvarying 

 constancy of gravitation ; the attraction of two particles being in direct proportion to their mass and in inverse 

 proportion to the square of their distance. This universal force of gravity is at work in the fall of an apple and 

 the tidal wave no less than in the course of the planets round the sun and the movements of all the heavenly bodies. 

 In fundamental opposition to the theory of vibration, or the kinetic theory of substance, we have the modern 

 theory of ' condensation,' or the pyknotic theory of substance. It is most ably estabUshed in the suggestive work of 

 J. C. Vogt on " The Nature of Electricity and Magnetism on the Basis of a Simplified Conception of Substance " (1891). 

 Vogt assumes the primitive force of the worid, the universal prodynamis, to be, not the vibration or oscillation of 

 particles in empty space, but the condensation of a simple primitive substance, which fills the infinity of space in 

 an unbroken continuity. Its sole inherent mechanical form of activity consists in a tendency to condensation 

 or contraction, which produces infinitesimal centres of condensation ; these may change their degree of thickness, 



