ade by the commander himself, i.e., his decision that
no sound solution for the basic problem can be found. The new problem
is one for the commander himself to solve, i.e., it cannot properly be
delegated to a subordinate for solution, because its solution is
necessary as a basis for the commander's detailed plan. For these
reasons the new problem is, by definition (page 106), a subsidiary
problem, of the type distinctive of the second step.

At what point in the solution of the original problem does the
commander abandon the basic problem and proceed with the solution of
the new, subsidiary problem which has arisen as described? There are
various possible answers, all with a basis of reason, to this
question.

From the standpoint of theoretical precision, it might be said that
the basic problem is abandoned when the conclusion is reached that its
motivating task cannot be accomplished. It might also be said that the
basic problem is abandoned when the conclusion is reached that the
commander can in no way contribute toward the accomplishment of the
motivating task.

Practical experience indicates, however, that the basic estimate can
profitably be utilized until the conclusion is reached that no
contribution can be made to the purpose of the mission. At this point
a new estimate, subsidiary to the basic estimate, necessarily begins.
This view is confirmed, theoretically, by the fact that, at this point
in the procedure, a radical change occurs with respect to the
appropriate effect desired. In such circumstances, the commander
concludes that he cannot contribute, in any degree, to the
accomplishment of his immediate superior's general plan.

The incentive for the solution of the subsidiary problem will
therefore arise, on the basis thus adopted, when the commander has
concluded that he cannot contribute to the accomplishment of his basic
mission, and that he is under the necessity of evolving a new mission
for himself. His basic Decision (see discussion, hereafter, of Section
V of the Estimate Form) will reflect this conclusion and will thereby
afford him a basis for the solution of his subsidiary problem.

Problems of the foregoing nature, where the commander justifiably
departs from his instructions, are not unusual during the first step.
However, they are scarcely typical of that step so long as an
organized chain of command is in effective operation. In the more
usual case, the commander, at this point in his