688 ae The Relations of Mind and Matter. [July, 
very evidently does in the cerebral cells. There are possibly no 
actual nerve termini anywhere within the body, but simply occa- 
sional resistance nodes, in some of which a single inflowing cur- 
rent may be divided between several outgoing channels, but in 
many or all of which the current is checked and partly converted 
into some other mode of motion. 
It is not necessary here to go into any minute description of 
the nervous system. In man it is virtually double. In addition 
to the external sensory and motor system, there is a secondary 
system which is devoted to the needs of the digestive cavity and 
to other internal duties. These systems are similar in general 
make-up, consisting of ganglia and communicating fibers, which 
extend partly to muscles and partly to the epithelial layer. But 
they have marked differences. The sympathetic has no central 
ganglion answering to the cerebrum. Its operations are all per- 
formed without consciousness except through the occasional aid 
of its cerebral nerve connections. And in its nerve fibers the 
axis cylinder is destitute of a medullary sheath. Some writers 
consider that its operations may have been originally conscious 
and have beccme unconscious and simply reflex through inces- 
sant repetition. Yet this is very doubtful. It presents every . 
appearance of being a survival of a primitive nerve condition, be- 
yond which it has not greatly developed. Consciousness is a con- 
dition that must have been originally vague and generalized, and 
which but slowly grew specialized with the gradual centralization 
of the nervous system. We cannot imagine it as retrograding 
and disappearing in any developing nervous system. In fact, the 
system of intestinal nerves has never become centralized and defi- 
nite. Such consciousness as it may possess retains its original 
vagueness. Its functional existence is perhaps as ancient as that 
of the external nerve system, but its development has been much 
slower. When the latter had advanced to the condition of dis- 
tinct nerves and ganglia, the former yet remained in the primitive 
stage of cell conduction. The nerves of external sensation have 
gained an insulating sheath while those of intestinal sensation 
remain naked. The one has become definitely centralized while 
the other yet lacks special organization. These results flow from 
_ their difference of duties, which in the one case are simple and 
unvarying, in the other complex and excessively varied, As a 
result such consciousness as may exist in the intestinal system 
