ce and
endeavoring to eliminate it, when reasoning out the desirability or
undesirability of a certain weapon or a certain method. Of course,
every thoughtful person realizes that few effects in life are due
to one cause only, and that most effects are due to a combination
of many causes; so that, if any weapon or method succeeds or fails,
it is illogical to infer from that one fact that the weapon or
method is good or bad. A common illustration is the well-known
fact that a marksman may hit the target when his aim is too high
or too low, provided that he has erroneously set his sight enough
too low or too high to compensate; whereas if he had made only one
error instead of two, he would have missed. "Two wrongs cannot
make a right," but two errors can compensate each other, and often
do. The theory of the Probability of Errors recognizes this. In
fact, if it were not true that some errors are plus and some minus,
all errors in gunnery (in fact in everything) would be additive
to each other, and we should live in a world of error.

The partial advantage of the game-board over the occurrences of
actual war, for the purpose of studying strategy, lies largely in
its ability to permit a number of trials very quickly; the trials
starting either with identical situations, or with certain changes in
conditions. Of course, the game-board has the tremendous disadvantage
that it presents only a picture, and does not show a real performance;
but the more it is used, and the more fleets and game-boards work
together, the more accurate the picture will become, and the more
correctly we shall learn to read it.

One limitation of the game-board is that it can represent weather
conditions only imperfectly--and this is a serious limitation that
mayor may not be remedied as time goes on. The theory of the game-board
is in fact in advance of the mechanism, and is waiting for some
bright inventive genius for the remedy. Until this happens, the
imagination must do the best it can, and the effect of a certain
kind of weather under the other conditions prevailing will have
to be agreed upon by the contestants.

The term "war game" is perhaps unfortunate, for the reason that
it does not convey a true idea of what a "war game" is. The term
conveys the idea of a competitive exercise, carried on for sport;
whereas the idea underlying the exercise is of the most serious
kind, and has no element of sport about it, except the element that
compe