Examining next what is the natural order of intellectual progress among
mankind, M. Comte observes, that as their general mode of conceiving the
universe must give its character to all their conceptions of detail, the
determining fact in their intellectual history must be the natural
succession of theories of the universe; which, it has been seen,
consists of three stages, the theological, the metaphysical, and the
positive. The passage of mankind through these stages, including the
successive modifications of the theological conception by the rising
influence of the other two, is, to M. Comte's mind, the most decisive
fact in the evolution of humanity. Simultaneously, however, there has
been going on throughout history a parallel movement in the purely
temporal department of things, consisting of the gradual decline of the
military mode of life (originally the chief occupation of all freemen)
and its replacement by the industrial. M. Comte maintains that there
is a necessary connexion and interdependence between this historical
sequence and the other: and he easily shows that the progress of
industry and that of positive science are correlative; man's power to
modify the facts of nature evidently depending on the knowledge he has
acquired of their laws. We do not think him equally successful in
showing a natural connexion between the theological mode of thought and
the military system of society: but since they both belong to the same
age of the world--since each is, in itself, natural and inevitable, and
they are together modified and together undermined by the same cause,
the progress of science and industry, M. Comte is justified in
considering them as linked together, and the movement by which mankind
emerge from them as a single evolution.

These propositions having been laid down as the first principles of
social dynamics, M. Comte proceeds to verify and apply them by a
connected view of universal history. This survey nearly fills two large
volumes, above a third of the work, in all of which there is scarcely a
sentence that does not add an idea. We regard it as by far his greatest
achievement, except his review of the sciences, and in some respects
more striking even than that. We wish it were practicable in the compass
of an essay like the present, to give even a faint conception of the
extraordinary merits of this historical analysis. It must be read to be
appreciated. Whoever disbelieves that the philosophy