ORGANS OF SPACE AND 'TIME. 287 



so specializes and intensifies our ideas, and is so connected with many 

 of our most highly cherished recollections, that, even were the evidence 

 in its behalf far weaker than it actually is, we should look without favor 

 on any attempt to invalidate the doctrine, and, if forced to do so, should 

 abandon it with regret. The pantheistic is a grand but cold philosoph- 

 ical idea ; the anthropomorphic embodies our recollections, and restores 

 to us our dead. The one is the dream of the intellect, the other is the 

 hope of the heart. 



We have thus traced out the essential elements of the nervous ma- 

 chine in its highest complexity, and shown its gradual rise imperfection 

 from the purely automatic to the influential. We may there- jj 

 fore comprehend the difficulties under which metaphysicians tions. 

 labor, who confound all these parts and all these functions together, and 

 pass over as of no account the guiding indications which are furnished 

 by the study of structure. It is not difficult for the physiologist, en- 

 lightened by the knowledge he possesses, to recognize the various points 

 at which these philosophers go astray the point at which their theories 

 cease to be representations of the truth. He acknowledges the existence 

 of an external nature, and equally the existence of an immaterial spirit, 

 and to their action on or relation to each other he traces the resulting 

 phenomena. He admits that, among certain classes of life, every motion 

 and every sensation is due to external nature alone, but to these purely 

 automatic groups man does not belong. He repudiates the doctrines of 

 the idealist, because, though they may maintain themselves in the uncer- 

 tainties of metaphysical argument, they are dissipated at once in the more 

 severe trial of anatomical discussion. 



There are two fundamental ideas essentially attached to all our per- 

 ceptions of external things: they are SPACE and TIME, and Pro vision in the 

 for these an early provision is made in the nervous mechan- ^^^lf tfim 

 ism, while yet it is in an almost rudimentary state. The space and time. 

 development of the eye and the ear, as we shall more particularly find 

 when we come to the description of these organs, is for this purpose. In 

 a philosophical respect the eye is the organ of space, and the ear of time ; 

 the perceptions of which, by the elaborate mechanism of these structures, 

 become infinitely more precise than would be possible if the sense of 

 touch alone were resorted to. The indications thus gathered are trans- 

 mitted by the optic and auditory nerves respectively to the brain. 



In its highest condition of development, the nervous mechanism has a 

 threefold operation, objective, subjective, and impersonal. Objective, sub- 

 Objective ideas arise in external facts ; subjective in register- fa tl er&maio 

 ed impressions ; the impersonal, as, for example, the abstract erations. 

 truths of geometry, issue of pure reason, and are therefore to be attrib- 

 uted to the essential nature of the soul. Of these three elementary con- 

 stituents all human knowledge consists. 



