The Wealth of Nations by Part 5 Chapter 1 Page 29

presence, can never have the same disposition to ready obedience, with those whose whole life and conduct are every day directed by him, and who every day even rise and go to bed, or at least retire to their quarters, according to his orders.

In what is called discipline, or in the habit of ready obedience, a militia must always be still more inferior to a standing army than it may sometimes be in what is called the manual exercise, or in the management and use of its arms. But in modern war the habit of ready and instant obedience is of much greater consequence than a considerable superiority in the management of arms.

Those militias which, like the Tartar or Arab militia, go to war under the same chieftains whom they are accustomed to obey in peace are by far the best.