"On Strategy" (1871), as translated in Moltke on the Art of War: Selected Writings (1993) by Daniel J. Hughes and Harry Bell, p. 124
War is a matter of expedients.
As quoted in "Nothing Went According To Plan" by Jim Lacey in TIME magazine (15 April 2003)
If in war, from the beginning of the operations, everything is uncertain except such will and energy as the commander carries in himself, there cannot possibly be practical value for strategy in general principles, rules derived from them and systems built up upon the rules. … Strategy is a system of expedients. It is more than science, it is the translation of science into practical life, the development of an original leading thought in accordance with the ever-changing circumstances.
As quoted in Government and the War (1918) by Spenser Wilkinson
As quoted in Prussia : The Perversion of an Idea (1994) by Giles MacDonogh, p. 166 The wordplay with wägen and wagen, weigh and venture ("ehe wäg's dann wag's") is much older than Moltke -->
Kontext: Strategy is a system of expedients; it is more than a mere scholarly discipline. It is the translation of knowledge to practical life, the improvement of the original leading thought in accordance with continually changing situations.