The materialists should not too mincingly chop logic over the validity of their own reasoning. If they force upon us their conclusions respecting statical aggregates, or crystalline forms, let them accept the inductions that inevitably follow in the case of dynamical aggregates, or living organisms. Beggars of conditions should not be choosers of conditions, nor should they be al lowed to dodge equivalent judgments where the validity of one proposition manifestly rests upon that of another. If they insist upon the presence of a chemical unit, or, worse still, a crystalline "germ" or unit, in the case of statical aggregations, they are effectually estopped from denying the presence of vital units in dynamical aggregations. And if they further force upon us the conviction that the process of aggregation, when once determined, remains in the one case, eternally fixed and certain, they should not be permitted to turn round and insist that, in the other case, there is nothing fixed and certain, but all is variability, change, uncertainty of specific forms. If vital units have only a hypothetical existence, then chemical units, statical units, and morphological units, should fall into the same categories of judgment. A great deal of needless ingenuity has been wasted, both by the vitalists and materialists, in formulating impossible definitions of life--in attempts to tell us what life is. But Mr. Herbert Spencer is believed, by his many admirers, to have hit upon the precise explanatory phrases necessary to convey its true definitional meaning. He defines it as "_the continuous adjustment of internal relations to external relations_." This definition, when first formulated, was received by all the materialists of Europe with the wildest enthusiasm. It was absolutely perfect. All the phenomenal facts of life fitted into it, as one box, in a nest of them, fitted into another. The universal world was challenged to show that any other phenomenal fact than the one of life would fit into this prodigious formula of Mr. Spencer. The London "Times" tried its hand on it, but only in a playful way. It said: "All the world, or at least all living things, are nothing but large boxes containing an infinite number of little boxes, one within the other, and the least and tiniest box of all contains the germ,"--the elementary principle of life. But this was hardly a legitimate characterization. A nest of boxes presents no idea of "continuous adjustment," nor are the internal relations of one box adjusted to the external relations of another. The definition is really that of a piece of working machinery--any working machinery--and was designed to cover Mr. Spencer's theory of "molecular machinery" as run by molecular force.