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Classification of the Sci.
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These categories of purpose must be categories of every system of natural classification, so far as that classification expresses the development of a purpose working upon a unvarying condition of matter, or working upon conditions whose gradual changes and revolutions are sufficiently slow to allow of the purpose taking its full development. In some form they must appear in every natural classification,—be it of dances or be it of battles; or at least, so one may presume. But that form can hardly fail to be very different in case nothing interferes with the prosecution of a purpose and in case plans are liable to be deranged or frustrated at every step by unexpected emergencies. These categories must be expected to show themselves not only in true natural classification, but also in mistaken attempts at natural classification,—sometimes even more clearly. For they have their origin in the neces-