PHYSIOLOGY OF CONSCIOUSNESS 231 



the moment even physiologists touched " mental " 

 phenomena they adopted another language than that 

 used in their own work. He found by experiments on 

 the salivary glands that reflex excitations could be made 

 to depend on linked reflex excitations — that is, by reflexes 

 conditioned by other reflexes. A dog's glands can be 

 educated to act not only by the presentation of food but 

 on the excitation of them by the sound of a bell. A bell 

 of a few more or less vibrations fails to produce salivary 

 action. A time factor can be introduced and the glands 

 made to act five minutes, say, after the bell is struck. 

 At each introduction of a new element into the linked 

 reflexes the process is more and more " conditioned," and 

 more and more easily interrupted by some accidental or 

 purposed stimulation. This complex of reflexes becomes 

 at last " intelligence." 



It is commonly said that reflexes are nervous units. 

 It is, however, sounder to regard the real nervous, or 

 cerebral, or " mental " unit as the native irritability of 

 the cell. If this is so the rise from reaction in the cell to 

 a simple reflex, and from that to reflexes conditioned by 

 others, and further to the most complex set of reflexes 

 imaginable in the highest brain, should show no break. 

 That we are unable to foretell the reaction in the cases 

 of high reflex combinations goes for nothing. It is, 

 indeed, our incapacity to do so which shows the nature 

 of words. They are sound signals which produce or tend 

 to produce reactions, thus becoming, on this analysis, links 

 in reflex reactions. Their motor products depend entirely 

 on the nature and quality of the organism concerned. 

 Thus to mention the word " faery " in a mixed gathering 

 may produce a " fairy " story from one and induce 

 another to quote " perilous seas and faery lands forlorn." 



