duct of a
single impulse, acting through all the partial agencies, and can
therefore be most easily traced by studying them together. Could it even
be detected in them separately, its true nature could not be understood
except by examining them in the _ensemble_. In constructing, therefore,
a theory of society, all the different aspects of the social
organization must be taken into consideration at once.

Our space is not consistent with inquiring into all the limitations of
this doctrine. It requires many of which M. Comte's theory takes no
account. There is one, in particular, dependent on a scientific artifice
familiar to students of science, especially of the applications of
mathematics to the study of nature. When an effect depends on several
variable conditions, some of which change less, or more slowly, than
others, we are often able to determine, either by reasoning or by
experiment, what would be the law of variation of the effect if its
changes depended only on some of the conditions, the remainder being
supposed constant. The law so found will be sufficiently near the truth
for all times and places in which the latter set of conditions do not
vary greatly, and will be a basis to set out from when it becomes
necessary to allow for the variations of those conditions also. Most of
the conclusions of social science applicable to practical use are of
this description. M. Comte's system makes no room for them. We have seen
how he deals with the part of them which are the most scientific in
character, the generalizations of political economy.

There is one more point in the general philosophy of sociology requiring
notice. Social phaenomena, like all others, present two aspects, the
statical, and the dynamical; the phaenomena of equilibrium, and those of
motion. The statical aspect is that of the laws of social existence,
considered abstractedly from progress, and confined to what is common to
the progressive and the stationary state. The dynamical aspect is that
of social progress. The statics of society is the study of the
conditions of existence and permanence of the social state. The dynamics
studies the laws of its evolution. The first is the theory of the
_consensus,_ or interdependence of social phaenomena. The second is the
theory of their filiation.

The first division M. Comte, in his great work, treats in a much more
summary manner than the second; and it forms, to our thinking, the
weakest part of the