Command and prohibition operate on the same plane
as the impulse of want, — that is, on the sense of percep-
tion. They exhibit then to the individual the legal and
actual consequences of the observance or non-observance
of legal commands or prohibitions. They thereby create
motives which are usually sufficient to restrain incom-
patible acts, and to bring about the doing of that which
the social life of man or the view of the community
requires. The bringing to bear of motive against motive
is the political side of legal order. It has for its design
the institution and maintenance of peace and the
advancement of civilization and humanity.
It is a matter not to be disregarded that the impulse
of want and legal rules both operate through the medium
of the faculty of perception. Legal commands and
prohibitions are inoperative against beings without the
faculty of perception, or with undeveloped faculties of
perception. Accordingly, acts of beings with no co-



LAW AND ITS SOURCES 51

ordination between the perceptive faculties and the
excitation of the motor nerves necessary for the comple-
tion of a [juristic] act; or lacking a psychological free-
dom of choice, are not acts in the law. 1 Incapacity for
responsibility and the resulting invalidity of juristic
acts of the insane illustrate this point.
