THE NERVOUS SYSTEM. 34-5 



in the most complicated beings ; so that man is said to have 

 five external senses touch, taste, smell, hearing, and sight. The 

 word touch is used to signify both the power of sensation on the 

 contact of bodies, and also that general feeling which pervades 

 every part, tind is able to produce endless varieties of sensations 

 from diversity of causes. If the external world, however, excites 

 merely sensations, the knowledge is very scanty, and the execution 

 of the will and the motives are as limited. But as we ascend in 

 the scale of animals, faculty after faculty is added : so that various 

 properties of the external world are learnt, form is distinguished, 

 and symmetry, and distance : the relation of colours, sounds, and 

 numbers ; and a power is at the same time given for viewing, as a 

 whole, any object which excites these sensations and inner feelings, 

 - so many internal senses, as some have named these powers. 



As we continue to rise, powers still higher are given ; the 

 power of viewing all things in connection, of comparing, contrast- 

 ing, inferring : and in some individuals these, to which the term 

 intellectual powers is especially given, are of great strength. At the 

 same time, motives are given in increased numbers. The lowest 

 animal has little more than a desire for food or life or an agree- 

 able sensation, and an aversion from uneasiness : but to some, a 

 desire of an act for the purpose of continuing the species ; to 

 others, a desire to construct a habitation, and in a particular 

 manner; to some, a desire to attack and destroy, &c., is given,- 

 desires few or more and in various proportions. These are all 

 internal feeling, or so much consciousness. Now, any feeling may 

 not only occur, so that sensation, perception, or consciousness 

 are common attributes ; but, when a feeling occurs which had 

 occurred before, the circumstance that it is the recurrence of a 

 feeling may be noticed. An odour may be recognised as one 

 smelt before ; a desire, a thought, as one experienced before. 

 The philosopher may recognise a great thought as not new to 

 him ; and the lowest animal may probably be aware that a savour 

 is the same it experienced once before. This is called memory. 

 The impression may return in an obscure manner, without the 

 recurrence of the original cause : so that we feel we had it before, 

 we remember having witnessed something. Feelings from even 

 external causes may recur without the recurrence of the external 

 cause. ' The impression is not so lively as when excited origin- 

 ally ; if we figure to ourselves a building which we have seen, 

 the feeling, though strong enough for thinking and discoursing 



