The important thing in strategy is to suppress the enemy's useful actions but allow his useless actions

Do not regret what you have done

From inside fortifications, the gun has no equal among weapons. It is the supreme weapon on the field before the ranks clash, but once swords are crossed the gun becomes useless.

Become acquainted with every art.

Do not let your opponent see your spirit

As far as Im concerned, I regret nothing.

There are many ways of understanding simple things, but generally the opposite is true for difficult ideas