Page:Popular Science Monthly Volume 3.djvu/723

Rh  position, Prof. Agassiz is never likely to show. This is largely because Lyell has always been a thinker of purely scientific habit, while Agassiz has long been accustomed to making profoundly dark metaphysical phrases do the work which properly belongs to observation and deduction. But, however we may best account for these idiosyncrasies, it remains most probable among those facts which are still future, that Prof. Agassiz will never advance any more crushing refutation of the Darwinian theory than the simple expression of his personal dislike for "mechanical agencies," and his belief in the "free manifestations of an intelligent mind." Were he only to be left to himself, such expressions of personal preference could not mar the pleasure with which we often read his exposition of purely scientific truths. But when he is brought before the public as the destroyer of a theory, the elements of which he has never yet given any sign of having mastered, he is placed in a false position, which would be ludicrous could he be supposed to have sought it, and which is, at all events, unworthy of his eminent fame.



"Natural science," says Du Bois-Reymond, "is a reduction of the changes in the material world to motions of atoms caused by central forces independent of time, or a resolution of the phenomena of Nature into atomic mechanics. . . . The resolution of all changes in the material world into motions of atoms caused by their constant central forces would be the completion of natural science."

Obviously, the proposition thus enounced assigns to physical 