Page:Popular Science Monthly Volume 3.djvu/713

Rh nothing is more certain than that a man's opinion may be eminently fallible, even with reference to matters which might appear to come directly within the range of his own specialty. Many people, I presume, think that, because Prof. Agassiz has made a specialty of the study of extinct and living organisms, because he has devoted a long and industrious life to this study, therefore his opinion with reference to the relations of present life upon the globe to past life ought to be at once conclusive. The fallacy of this inference becomes apparent as soon as we recollect that Profs. Gray, Wyman, Huxley, and Haeckel, who are equally well qualified to have an opinion on such matters, have agreed in forming an opinion diametrically opposite to that of Prof. Agassiz. But the fallacy may be shown independently of any such comparison. Even if all the foundations of certainty seem to be shaking beneath us when we say that an expert is not always the best judge of matters pertaining to his own specialty, we must still say it, for facts will bear us out in saying it. I have known excellent mathematicians and astronomers who had not the first word to say about the Nebular Hypothesis: they had never felt interested in it, had never studied it, and consequently did not understand it, and could hardly state it correctly. After a while one ceases to be surprised at such things. It is quite possible for one to study the structure of echinoderms and fishes during a long life, and yet remain unable to offer a satisfactory opinion upon any subject connected with zoology, for the proper treatment of which there are required some power of generalization and some familiarity with large considerations. Indeed, there are many admirable experts in natural history, as well as in other studies, who never pay the slightest heed to questions involving wide-reaching considerations; and who, with all their amazing minuteness of memory concerning the metamorphoses of insects and the changes which the embryo of a white-fish undergoes from fecundation to maturity, are nevertheless unable to see the evidentiary value of the great general facts of geological succession and geographical distribution, even when it is thrust directly before their eyes. To such persons, "science" means the collecting of polyps, the dissecting of mollusks, the vivisection of frogs, the registration of innumerable facts of detail, without regard to the connected story which all these facts, when put together, have it in their power to tell. And all putting together of facts, with a view to elicit this connected story, they are too apt to brand as unscientific speculation; forgetting that if Newton had merely occupied himself with taking observations and measuring celestial distances, instead of propounding an audacious hypothesis, and then patiently verifying it, the law of gravitation might never have been discovered. Herein lies the explanation of the twice-repeated rejection of Mr. Darwin's name by the French Academy of Sciences. The lamentable decline of science in France since the beginning of the Second Empire has been most conspicuously marked by the tendency of scientific