"Rat's head and ox's neck" means that, when we are fighting with the enemy and both he and we have become occupied with small points in an entangled spirit, we must always think of the Way of Strategy as being both a rat's head and an ox's neck. Whenever we have become preoccupied with small detail, we must suddenly change into a large spirit, interchanging large with small. This is one of the essences of strategy. It is necessary that the warrior think in this spirit in everyday life.
The "mountain-sea" spirit means that it is bad to repeat the same thing several times when fighting the enemy. There may be no help but to do something twice, but do not try it a third time. If you once make an attack and fail, there is little chance of success if you use the same approach again. If you attempt a technique which you have previously tried unsuccessfully and fail yet again, then you must change your attacking method. If the enemy thinks of the mountains, attack like the sea; and if he thinks of the sea, attack like the mountains.
The gaze should be large and broad. This is the twofold gaze "Perception and Sight". Perception is strong and sight weak. In strategy it is important to see distant things as if they were close and to take a distanced view of close things.