ARE ANUIALS AUTOMATONS? 731 



of analogy — taking into account that great doctrine of continuity 

 which forbids one to suppose that any natural phenomenon can come 

 into existence suddenly and without some j^recedent, gradual modifi- 

 cation tending toward it — taking that great doctrine into account (and 

 every thing we know of science tends to confirm it), and taking into 

 account on the other hand the incontrovertible fact that the lower 

 animals which possess brains at all possess, at any rate, in rudiments a 

 part of the brain, which we have every reason to believe is the organ 

 of consciousness in ourselves, then it seems vastly more probable that 

 the lower animals, although they may not possess that sort of con- 

 sciousness which we have ourselves, yet have it in a form proj)ortional 

 to the comparative development of the organ of that consciousness, 

 and foreshadow more or less dimly those feelings Avhich we possess 

 ourselves. I think that is, probably, the most rational conclusion that 

 can be come to. It has this advantage, that it relieves us of the very 

 terrible consequences of making any mistake on this subject. I must 

 confess that, looking at that terrible struggle for existence which is 

 everywhere going on in the animal world, and considering the fright- 

 ful quantity of pain which must be given and received in every part 

 of the animal world, I say that is a consideration which would in- 

 duce me wholly to adopt the view of Descartes. Yet I think it 

 on the whole much better to err on the right side, and not to con- 

 cur with Descartes on this point. But let me point out to you that, 

 although we may come to the conclusion that Descartes was wrong in 

 supposing that animals are insensible machines, it does not in the slight- 

 est degree follow that they are not sensitive and conscious automata ; in 

 fact, that is the view which is more or less clearly in the minds of every 

 one of us. When we talk of the lower animals being provided with 

 instinct, and not with reason, what we really mean is that, although 

 they are sensitive, and, although they are conscious, yet they do act 

 mechanically, and that their different states of consciousness, their 

 sensations, their thoughts (if they have them), their volitions (if they 

 have them), are the products and consequences of the mechanical ar- 

 rangements. I must confess that this popular view is to my mind the 

 only one which can be scientifically adopted. We are bound by every 

 thing we know of the operations of the nervous system to believe that, 

 when a certain molecular change is brought about in the central part 

 of the nervous system, that change, in some way utterly unknown to 

 us, causes that state of consciousness that we term a sensation. It is 

 not to be doubted that the impression excited by those motions which 

 give rise to sensation leaves in the brain molecular changes which an- 

 swer to what Haller called " vestigia rerumj'' and which that great 

 thinker David Hartley termed " vibratiuncles," which we might term 

 sensigenous molecular, and which constitute the physical foundation 

 of memory. Those same changes gave rise naturally to conditions of 

 pleasure and pain, and to those emotions which in ourselves we call 



