120 



Professor Huxley 



[March 7, 



take place in the sensiferous apparatus are continuous with, and 

 similar to, those which take place in the external world.* But with 

 the sensorium, matter and motion come to an end ; while phenomena 

 of another order, or immaterial states of consciousness, make their 

 appearance. How is the relation between the material and the imma- 

 terial phenomena to be conceived ? This is the metaphysical problem 

 of problems, and the solutions which have been suggested have been 

 made the corner-stones of systems of philosophy. 



Sensations of taste, however, are generated in almost as simple a 

 fashion as those of smell. In this case, the sense organ is the epithe- 

 lium which covers the tongue and the palate ; and which sometimes, 

 becoming modified, gives rise to peculiar organs termed " gustatory 

 bulbs," in which the epithelial cells elongate and assume a somewhat 

 rod-like form. Nerve fibres connect the sensory organ with the 

 sensorium, and tastes or flavours are states of consciousness caused by 

 the change of molecular state of the latter. In the case of the sense 

 of touch there is often no sense organ distinct from the general epider- 

 mis. But many fishes and amphibia exhibit local modifications of the 

 epidermic cells which are sometimes extraordinarily like the gustatory 

 bulbs ; more commonly, both in lower and higher animals, the effect 

 of the contact of external bodies is intensified by the development of 

 hair-like filaments, or of true hairs, the bases of which are in imme- 

 diate relation with the ends of the sensory nerves. Everyone must 



* The following diagrammatic scheme may help to elucidate the theory of 

 sensation : — 



Mediate Knowledge 



^ ^- ^^ Immediate 



Sensiferous Apparatus Knowledge 



Objects of Sense 



Hypothetical 

 Substance of 



Matter 



Eeceptive Transraissive Sensificatory Sensations and 

 (Sense Organ) (Nerve) (Sensorium) other States of 



Consciousness 



Hypothetical 



Substance of 



Mind 



Physical World 



Mental World 



Not Self 



Self 



Non-Ego or Object 



Ego or Subject 



Immediate knowledge is confined to states of consciousness, or, in other words, to 

 the phenomena of mind. Knowledge of the physical world, or of one's own body 

 and of objects external to it, is a system of beliefs or judgments based on the 

 sensations. The term "self" is applied not only to the series of mental phe- 

 nomena which constitute the ego, but to the fragment of the physical world 

 which is their constant concomitant. The corporeal self, therefore, is part of the 

 non-ego ; and is objective in relation to the ego as subject. 



