Conversation so far:
What was the philosophy of Miyamoto Musashi?
Miyamoto Musashi was the founder of the Niten-Ichi-Ryū-School or Nito-Ichi-ryū style of swordsmanship.
Do all of Miyamoto Musashi's philosophies relate to war?
Musashi seems to take a very philosophical approach to looking at the craft of war“

Question: What is an interesting aspect of his philosophy?
Self-contained rewrite: What is an interesting aspect of Miyamoto Musashi's philosophy?