138 POPULAR SCIENCE MONTHLY. 



the facts of instinct, while these in their turn receive their only rational 

 explanation in this theory of inherited acquisition. But the difficulty 

 of the undisciplined mind lies, as we have said, in an inability to grasp 

 the full significance of the doctrine that, in an individual life, it is the 

 physical part alone that endures from day to day ; that, strictly speaking, 

 we cannot feel the same feeling or think the same thought twice over; 

 that only as by pulling the bell-cord to-day we can, in the language of 

 ordinary discourse, produce the sound we heard yesterday, can we, while 

 the established connections among the nerves and nerve centers hold, live 

 our experiences over again. 



This doctrine of inherited acquisition, then, is, to say the least, a 

 good working hypothesis in explanation of all those facts of instinct 

 that may be conceived as built up, compounded out of, the accumulated 

 experiences of innumerable generations. So far good. But it will occur 

 to every reader that the peculiar depths of animal psychology are not 

 yet explored. Two classes of phenomena still lie in the dark. First, 

 there are the many extraordinary and exceptional feats of dogs and 

 other animals, which seem to be constantly falling under the observation 

 of everybody except the few that are interested in these matters. 

 Second, all the more wonderful instincts, especially those of insects, are 

 such that it is hard, if at all possible, to conceive how they ever could 

 have been derived from experience. 



With regard to the first, it is not desirable to say much. Though 

 volumes of marvelous stories have been written, I am not aware that 

 any careful experiments have been tried, and, as the performances in 

 question are of an exceptional character, it is perhaps but scientific 

 caution not as yet to put too much stress on them. For my own part, 

 though I have been very intimate with dogs, I have been singularly 

 unfortunate in having never witnessed any of their more incompre- 

 hensible clairvoyant-like achievements. I have known them to do many 

 surprising things, but I have always found that they had, or might have 

 had, something to go upon — enough, coupled with quick intelligence, to 

 account for their exploits. What may be said in this connection, if, 

 indeed, it be prudent to say anything, is that, while we certainly cannot 

 have all the data of experience from without of all the vastly different 

 living things which people the earth, the air, and the ocean — while we 

 certainly can have no trace of many feelings that arise from changes in 

 the organisms of the different creatures, and which, instinctively inter- 

 preted, start them on lines of action — a host of statements, generally 

 accepted as fact, suggest the opinion that even such animals as dogs, are 

 alive to, conscious, sensible of influences that scarcely affect us, or 

 wholly escape our cognition. If this be so, they have a basis of experi- 

 ence from which to start in their calculations that we want, and, if so, 

 well may their actions seem to us, as Mr. Mill said, hopelessly inexpli- 



