It's important to make an effort under any circumstance - stagnant, sickness, being in an unstable lifestyle, even when society is insane. You should consider such periods as an omen before you move. When you are stuck on something, it is important to hold to your purpose but not press onward against the current. When you can't move at all, try to concentrate, continuing forward as if in a boat switching to a stronger motor. The keiko that is most important when you cannot move is kage no keiko [shadow training].

The simplest is always the most difficult.

If you do not let go of thinking about forms, you will not understand what I am showing.

No more talk. I'm sick of people talking. Train.

Always be able to kill your students

The first priority to the ninja is to win without fighting.

Forget your sadness, anger, grudges and hatred. Let them pass like smoke caught in a breeze. Do not indulge yourself in such feelings.