to the
authority of any one who makes a profession of the art. In the laying
out of a park a landscape architect may prefer single trees and open
spaces, where the neighbors and abutters prefer a grove. In the long run
his taste is no better than theirs, though he may argue as if they were
ignorant and uncultivated because they disagree with him. In all such
cases, unless there is some consideration of practical expediency, such
as letting the southwest wind blow through in summer, arguments can do
little except to make and keep everybody angry. Their chief value is to
make us see things which perhaps we had not thought of.

In practice these three kinds of arguments, which turn on moral,
practical, and aesthetic considerations, tend to be much mingled. The
human mind is very complex, and our various interests and preferences
are inseparably tangled. The treacheries of self-analysis are
proverbial, and are only less dangerous than trying to make out the
motives of other people. Accordingly we must expect to find that it is
sometimes hard to distinguish between moral and aesthetic motives and
practical, for the morality and the taste of a given people always in
part grow out of the slow crystallizing of practical expediencies, and
notions of morality change with the advance of civilization.

Furthermore, one must never forget that an argument of policy which
does not involve and rest on subsidiary questions of fact is rare; and
the questions of fact must be settled before we can go on with the
argument of policy. Before this country can intelligently make up its
mind about the protective tariff, and whether a certain rate of duty
should be imposed on a given article, a very complex body of facts
dealing with the cost of production both here and abroad must be
settled, and this can be done only by men highly trained in the
principles of business and political economy. Before one could vote
intelligently on the introduction of a commission form of government
into the town he lives in he must know the facts about the places in
which it has already been tried. It is not too much to say that there is
no disputed question of policy into which there does not enter the
necessity of looking up and settling pertinent facts.

On the other hand, there are some cases of questions of fact in which
our practical interests deeply affect the view which we take of the
facts. In all the discussions of the last few years about federal
s