SCIENTIFIC RESEARCH 261 



arduous, is still the most wholesome of all activities. How 

 to realize the old Greek ideal of the sane mind in the healthy 

 body is still afar off. Present results indicate that heredity, 

 and not environment or education, leads to permanent 

 progress. If this is so, the application of the facts of heredity 

 to our species will be one of the great problems of the future. 

 We see now that we are on the right track, and that an ade- 

 quate knowledge, and hence control, of heredity may be 

 possible sooner than we had thought. 



Returning to the main contention, what we have seen in 

 the history of man's study of the microorganisms, in a more 

 restricted case like the fresh- water mussel, and in the broad 

 field of heredity, will be found in other lines. Facts appar- 

 ently remote from present needs come to be the very life 

 blood of subsequent generations. There are, doubtless, 

 barren fields, but almost any facts of nature are worth 

 studying, since only by continuous searching do we find that 

 for which we seek. If a child is lost on a mountain and there 

 are searching parties out beating the bushes, now here, now 

 there, or systematically covering the ground, the one who 

 actually finds the child may be rewarded; when in reality 

 it is largely an accident that he rather than another suc- 

 ceeded in the quest. It is more than likely the credit belongs 

 to another who so organized the hunt that nothing could 

 be overlooked. In our quest for facts, we must so advance 

 that no spot is left wholly unexplored; for we cannot tell 

 what importance any part of the field may assume. We 

 cannot afford to concern ourselves to-day merely with what 

 seems useful, since the more important advances of the past 

 have commonly been made through fields which at first 

 gave small promise of value. 



To some extent the needs of practical life have induced 

 men to explore the unknown territory of nature. But to a 

 greater extent investigators have been led into this terri- 

 tory by their attempts to learn more of nature, irrespective 

 of utilitarian values. We should, therefore, spare no effort 



