erefore, are a remote condition of the clover crop.
Again, the communication of thought by speech is an example of something
so common that it seems to need no explanation; yet to explain it is a
long story. A thought in one man's mind is the remote cause of a similar
thought in another's: here we have (1) a thought associated with mental
words; (2) a connection between these thoughts and some tracts of the
brain; (3) a connection between these tracts of the brain and the
muscles of the larynx, the tongue and the lips; (4) movements of the
chest, larynx and mouth, propelling and modifying waves of air; (5) the
impinging of these air-waves upon another man's ear, and by a complex
mechanism exciting the aural nerve; (6) the transfer of this excitation
to certain tracts of his brain; (7) a connection there with sounds of
words and their associated thoughts. If one of these links fail, there
is no communication.

Thirdly, the subsumption of several laws under one more general
expression.

The tendency of bodies to fall to the earth and the tendency of the
earth itself (with the other planets) to fall into the sun, are subsumed
under the general law that 'All matter gravitates.' The same law
subsumes the movements of the tide. By means of the notion of specific
gravity, it includes 'levitation,' or the actual rising of some bodies,
as of corks in water, of balloons, or flames in the air: the fact being
that these things do not tend to rise, but to fall like everything else;
only as the water or air weighs more in proportion to its volume than
corks or balloons, the latter are pushed up.

This process of subsumption bears the same relation to secondary laws,
that these do to particular facts. The generalisation of many particular
facts (that is, a statement of that in which they agree) is a law; and
the generalisation of these laws (that is, again, a statement of that in
which they agree) is a higher law; and this process, upwards or
downwards, is characteristic of scientific progress. The perfecting of
any science consists in comprehending more and more of the facts within
its province, and in showing that they all exemplify a smaller and
smaller number of principles, which express their most profound
resemblances.

These three modes of explanation (analysis, interpolation, subsumption)
all consist in generalising or assimilating the phenomena. The pressure
of the air, of a liquid, and motion in the direction of least
r