Direct experience is inherently too limited to form an adequate foundation either for theory or for application. At the best it produces an atmosphere that is of value in drying and hardening the structure of thought. The greater value of indirect experience lies in its greater variety and extent. History is universal experience, the experience not of another, but of many others under manifold conditions.
B. H. Liddell HartThe unexpected cannot guarantee success, but it guarantees the best chance of success.
B. H. Liddell HartThe blurring of the line between policy and strategy] encouraged soldiers to make the preposterous claim that policy should be subservient to their conduct of operations, and (especially in democratic countries) it drew the statesman on to overstep the definite border of his sphere and interfere with his military employees in the actual use of their tools.
B. H. Liddell HartThe more closely [the German army] converged on [Stalingrad], the narrower became their scope for tactical manoeuvre as a lever in loosening resistance. By contrast, the narrowing of the frontage made it easier for the defender to switch his local reserves to any threatened point on the defensive arc.
B. H. Liddell Hart