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.
No kind of shape, no kind of design or kind of picture or other work of art can be beautiful. No kind of color is beautiful. Beauty comes always from the singularity of things. Two things which happen to be closely similar in size, color, insurance value, smell, weight, or shape, may both seem equally beautiful. It is not therefore to be deduced that, say, a smell of turpentine is a necessary prerequisite of beauty; and nor is the fact that the two things' shapes are measurably within a millimeter of each other. They might still be as different as chalk and cheese: they might differ hugely in surface quality so that one lived and the other was dead. One judges a man by what he is, by his individuality, his idiosyncrasy; not by his measurable properties or measurable behavior or by the shape of his nose or the description in his passport. So with a work of art.