The primary thing when you take a sword in your hands is your intention to cut the enemy, whatever the means. Whenever you parry, hit, spring, strike or touch the enemy’s cutting sword, you must cut the enemy in the same movement. It is essential to attain this. If you think only of hitting, springing, striking or touching the enemy, you will not be able actually to cut him.
The McNamara fallacy, named for Robert McNamara, the US Secretary of Defense from 1961 to 1968, involves making a decision based solely on quantitative observations (or metrics) and ignoring all others. The reason given is often that these other observations cannot be proven.
The fallacy refers to McNamara's belief as to what led the United States to defeat in the Vietnam War—specifically, his quantification of success in the war (e.g., in terms of enemy body count), ignoring other variables.
The contents of the city's images which are referable to physical forms can conveniently be classified into five types of elements: paths, edges, districts, nodes, and landmarks.
Paths are the channels along which the observer customarily, occasionally, or potentially moved.
Edges are the linear elements not used or considered as paths by the observer. They are the boundaries.
Districts are the medium-to-large sections of the city, conceived of as having two-dimensional extent.
Nodes are points, the strategic spots in a city into which an observer can enter, and which are the intensive foci to and from which they are traveling.
Landmarks are another type of point-reference, but in this case the observer does not enter within them, they are external. They are usually a rather simply defined physical object: building, sign, store, or mountain.