482 



SCIENCE. 



[N. S. Vol. XV. No. 378. 



not help us out of the paradoxes of philoso- 

 phy, and make the way clear for an em- 

 bryological account of thinking men. 



2. The problem, of knoiving. 



Our sensations and thoughts and feel- 

 ings have not taken place anyhow and at 

 random. They have been so related in the 

 past that one has been a sign which has 

 led us to expect others, which have always 

 come about as we expected if our knowl- 

 edge has been sound and accurate. 



When they have thus come about, we 

 have known that this has not been our 

 doing. We have known too that it is 

 because it has not been our doing that nat- 

 ui'al knowledge has been useful to us. 



One of the most practical questions that 

 man can ask is this: When, and how far, 

 is our experience a sound basis for confi- 

 dence in things that we have not experi- 

 enced — such things, for example, as the 

 animal life of the Cambrian sea, the molec- 

 ular constitution of matter, and my own 

 embryonic history? Since an answer to 

 this question has been included in past 

 knowing, it must also be included in an 

 account of knowing. It is this question 

 that physical science undertakes to answer 

 by scientific discovery, but the biologist 

 must ask a still more difficult question: 

 How do living beings come to do uncon- 

 sciously, and without knowing it, the 

 things that are to their advantage? How 

 does a living being get safely through all 

 the chances and changes of life without 

 needing to run its nose into every danger 

 before it avoids it? How do some men 

 learn, from a single experience, what oth- 

 ers fail to find out after a lifetime of expe- 

 rience ? 



3. Our iiological education begins at an 

 early day. 



No institution, no period in the history 

 of science, no stage in intellectual develop- 

 ment, can lay claim to. the beginnings of 

 biological science. They are to be sought 



long before our entrance into laboratories; 

 long before the beginnings of book-learn- 

 ing. Even before we learned articulate 

 speech, the teacher whom the poet has 

 called the grand old nurse took us upon her 

 knee and began the wonderful story of 

 nature for our delight and profit and in- 

 struction; that story to which there is no 

 end; in which each chapter, as fresh and 

 new as the first, adds new meaning, new 

 usefulness to all we have been told. 



Part, at least, if not the whole, of our 

 early education was biological. We laid 

 the foundations of anatomy and experi- 

 mental physiology when we learned, 

 through repeated scientific experiments, 

 that it is through eyes that we see, through 

 ears that we hear, through hands that we 

 touch, and that it is good to see and hear 

 and handle things. We were no doubt 

 led, slowly and gradually, through innu- 

 merable scientific experiments, to the dis- 

 covery that, among the changes that go on 

 in nature, some are of peculiar interest 

 and importance to us; and we thus come 

 to set apart in our minds, from among the 

 things of which our senses tell us, certain 

 ones which seem, because of their clear 

 relation to our comfort and discomfort, 

 and because of the quickness with which 

 we learn how to make use of them, to per- 

 tain to ourselves, and to constitute our 

 bodies, as distinct from the world around 

 us, which we are thus led to set over 

 against ourselves, as a not-self. It seems 

 to me that it is in this way that we lay 

 a foundation, in the conception of a living 

 body, for all later study of biological sci- 

 ence, and no naturalist can doubt the great 

 and permanent value of this conception; 

 yet there is no more fruitful source of 

 paradox and contradiction and absurdity 

 than the words in which we attempt, at a 

 later stage, to describe this scientific dis- 

 covery; for while a scientific discovery is 

 part of the language of nature, our words 



