g, is the
reference of this individual notion to a class. Now the _class-notion_
is the same as the individual notion, less certain attributes as
_individual_ attributes, but gathered into a larger whole. This process
is plainly integration; we are rejecting from the new conception
whatever prevents enlarging the class. Each higher generalization
involves all the attributes of the lower, not individually, but
specifically or generically. In the final generalization, extension and
intension coalesce. Just as we reach the individual by differentiating a
universal through successive negations, we reach the universal again, by
integration, by successively denying the negations through which we just
now differentiated. The movement of the finite mind in reasoning is thus
from the individual through the universal to the individual again.

Science thus parts into two great branches--one seeking to establish
principles by what we have called integration, and the other the
elucidation of facts by _a priori_ reasoning instead of observation.
That is, the aim of true science is to free man from the restrictions of
the finite, and to place him in possession of the infinite--the closing
in of a lesser circle of infinite truth, yet never losing hold upon the
finite. In accordance with this view we see science pursuing its
integrations until it has identified as composing an essential unity all
the various manifestations of force. This is the finite becoming the
infinite, for unity is, in so far, infinity--God is one, a unity, not a
unit. But we also see science going beyond this point, and by a new
series of differentiations reaching truths new to experience, if indeed
not impossible to experience.

Between these two limits all knowledge is forever moving. It can never
rest. The tide of thought sweeps onward towards the infinite--God
following it to its final absorption into the _I Am_, simple
being,--while finite man, because of his finiteness, can only reach
those universals which are infinite only to human thought. Like men on a
journey we leave the train when we have reached our journey's end, but
the train passes on out of sight in the distance, sending back, now and
then, tokens of its progress, as it thunders over a bridge, or whistles
shrill as it nears some further stopping place, until at last all is
still, not because the train has stopped, but because we can follow it
no further with our senses. Even after science has re