446 BIOLOGY. 



system only between a special organ and the nervous 

 centre. 



2703. In itself the nervous system is an Indifference, 

 and such then are all the organs upon which it acts, 

 when regarded in reference to this operation ; they might, 

 through other functions, be polar. 



2704. The nervous system becomes differential either 

 through its two kinds of substances, or through extra- 

 neous influence ; in the first case it thinks or moves, in 

 the second it feels. 



2705. Sensation is in the nervous what motion is in 

 the fibrous system, namely, a polar condition, in which 

 the two ends have a tendency to come together, in order 

 to discharge or unload. 



2706. In the sensation the extremity of the nerves 

 strives to approach that of the brain ; it is therefore a 

 contractile effort in the nerves, like motion is in the 

 muscular fibre. Juxta-posited granules could not, how- 

 ever, shorten ; therefore, the already calculated polarity 

 courses over them. 



2707. All external stimuli act upon the nerves and 

 polarize them, but not the muscular fibres. 



2708. The fibre becomes directly polarized only 

 through the internal stimuli, or by the blood, galvanic 

 tension, &c. 



2709. The most general function of the nervous 

 system consists in its assuming polarity from the world, 

 and imparting this to other systems, apart namely, from 

 the alternate operation of its two substances. 



Nervous and Motor System. 



2710. The first system is that of motion. The 

 tranquil presence of the nerve in the fibre produces 

 indifference in the latter ; so that it has no susceptibility 

 for the polarization that is effected by the artery. Doubt- 

 less the arterial blood passes, for the most part, close by 

 the fibre through other capillary vessels. 



2711. But if the nerve be polarized it is then basic, 

 negative, and enters into opposition with the arterial 





