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.
"Artists need to be in there from the start, making the argument for quality. The key to this thing is, for example, if you give an engineer a set of criteria which does not include a quality quotient, as it were—that is, if this sense of the quality, the character of the place, is not a part of his original motivation—he will then basically put the road straight down the middle. He has no reason to curve it. But if I can convince him that quality is absolutely a worthwhile thing and we can work out a way in which the road can be efficient and also wander down by the river, then we essentially have both: he provides his sort of expertise in that the road works, I provide quality in that it passes by the river. In that way, art gets built into the criteria from the beginning rather than being added on afterward."