To train with him called for Purity of Character, that is to say "the search for perfection of technique and character," Honesty, to make sure our training had a useful purpose and not something that built false ego's but instead built confidence through hard work and strong fighting technique, Honor, to live by our word, not to be a burden on someone else and not to take advantage of the weak.
We trained with Zen philosophy in mind. Sensei Kimura would say "you want to learn Zen then look in the mirror. What do you see?" at that point, if you looked in the mirror then you were hooked for life. To keep on looking for your weaknesses and correct them, to find your strengths and improve them and to keep seeing something different every time you looked in the mirror.