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1908 Dec 1
Logic
I.i. 21

origins. Astronomy and geognosy were the first sci-
ences. The latter is now divided into geodesy (in the sense of
the study of the form and size of the entire level surface of which the
sea-level is a part, together with the explanation of its having that
form), physical geography, hydrography and oceanography, the
science of the tides, geology, etc. Such studies, which form the lowest order, are called descrip-
tive sciences; but a better designation would be explanatory
sciences; for mere description without explanation is the goal
of an art rather than of a science. We must however within this third order of science distinguish a descriptive family of science and an explanatory family. As an explanatory science
progresses it becomes acquainted with great numbers of more
or less similar objects, and thus tends to pass into the
second order, that of the Classificatory sciences. Each such sci-
ence seeks, in the first place, to form a scheme of classification