ANIMAL INTELLIGENCE. 219 



So that we thus see how animal instincts may arise in either of two 

 diflferent ways : for, on the one hand, they may arise from the perform- 

 ance of actions which were originally intelligent, but which b\' frequent 

 repetition have become automatic ; and, on the other hand, they may 

 arise from survival of the fittest, preserving actions which, although 

 never intelligent, yet happen to have been of benefit to the animals 

 which first chanced to perform them. But now let it be observed 

 that, although there is a great difference between these two kinds of 

 instincts if regarded psychologically, there is no difference between 

 them if regarded physiologically ; for, regarded physiologically, both 

 kinds of instincts are merely expressions of the fact that particular 

 nerve-cells and fibres have been set apart to perform their reflexes au- 

 tomatically — that is, without being accompanied by intelligence. 



So much, then, for what I have called the physiological basis of 

 mind; and, in now taking leave of this part of my subject, I should 

 like to point out that, in recognizing the indisputable fact of mind hav- 

 ing such a basis, we are not necessarily committing ourselves to the doc- 

 trine of materialism. That psychical phenomena are very intimately 

 associated with physical phenomena is a fact which does not admit of 

 one moment's dispute ; but concerning the nature of this association 

 Science must declare, not merely that it is at present unknown, but 

 that, so far as she is at present able to discern, it must forever remain 

 unknowable. The restless tide of intellect for centuries has onward 

 rolled, submerging in its every arm those strong and rugged shores 

 whose name is Why; but at the line where mind and matter meet there 

 rises, like a frowning cliff, a mighty mj^sterj^, and in the darkness of 

 the place we hear the voice of true Philosophy proclaim, " Hitherto 

 shalt thou come, but no farther, and here shall thy proud waves be 

 stayed." 



Passing on now to our review of comparative ps3^chology, the first 

 animals in which, so far as I can ascertain, we may be quite sure that 

 reflex action is accompanied by ideation, are the insects. For Mr. Dar- 

 win has observed that bees remember the position of flowers which they 

 have only several times visited, even though the flowers be concealed 

 by intervening houses, etc. Sir John Lubbock also has shown that, 

 after a very few individual experiences^ bees are able to establish a 

 definite association between particular colors on paper and food ; and 

 further that, after a, very few lessons, a bee may be taught to find its 

 way out of a glass jar. These observations would seem to prove that 

 the grade of intelligence is higher in some Articulata than it is among 

 the lower Vertebrata. For many of you will probably remember the 

 experiment of Prof. Mobius, which proved that a pike requires three 

 months to establish an association of ideas between particular kinds of 

 prey and the fact of their being protected by an invisible wall. This 

 fact was proved by the pike repeatedly dashing its nose against a glass 

 partition in its tank in fruitless efforts to catch minnows which were 



