“Even though in the spring winds flowers bloom and green increases, when the autumn frost comes, leaves fall and trees wither. This is the judgement of Heaven’s Way. There is logic in striking down something when it has peaked. When someone rides his luck and does evil, you strike him down when his evils have peaked. In that sense, using weapons is said to be also Heaven’s Way. At times, because of one man’s evil, thousands of people suffer. So you kill that one man in order to let the thousands live. Here, truly, the blade that deals death could be the sword that gives life”
-Yagyu Munenori, The Sword and the Mind (1632 AD).