Ninjutsu thinking came primarily from Buddhist and Confucian thinking. With a focus on rejecting selfish desires, embracing virtues and training the mind. Here are some things that made up the Correct Mind for Ninjutsu:
The “three diseases” of ninjutsu are:
1. To Fear
2. To Take the Enemy Lightly
3. To Think Too Much
The Book of Ninja asserts that all people are a mixture of two minds: Jishin and Doshin
Jishin is the mind of man; man’s natural state. It’s easily affected by what he sees and hears, worries about, indulges in, and is absorbed by. It’s given to lust and selfish desires. If you depend on your jishin, it will lead to ruin.
Doshin is the nature that knows what’s right and knows principles. Follow this righteous nature and have no selfishness. All people have a mixture of these two minds (according to the Book of Ninja).
A Mind Like Water
“If you have a sword in your spirit to cut off your doubt, any dream may be realized in your life.” ~The Book of Ninja
The method of ‘mind like water’ allows you to be free from the 3 diseases while you’re fighting. Your mind and body will be free to adapt.
The mind is like water or a mirror, which doesn’t move itself and is still and serene. It can be moved by wind or men and lose its stillness. When this happens, it no longer reflects things well. The mind should be clear and stable, reflecting whether things are right or wrong. You have an enemy or ally nowhere else but in your own mind.
The Present Mind
If your mind isn’t present, you can’t see even when you look, hear even when you listen or taste even if you eat. This presence of mind is wrapped up in the four virtues of: benevolence, righteousness, loyalty and faithfulness.
The Heart of an Iron Blade
The kanji or character that spells shinobi is made from the strokes for “heart” and “blade.” Heart is used because of the shinobi’s focus on courage and valor.
Bravery can be gained by rejecting brute courage, blind daring and hot-blooded rage. These things give strength for a little while, but they don’t last and are difficult to pair with a strong mind.
A wise man’s courage stems from duty. This kind of courage is compelling, never weakens and is detached from motive. If you use brute courage, you end up destroying yourself without damaging the enemy much.
You should still have a reasonable fear (common sense) and not ally with people who do stupid things. Also, unless you have benevolence, loyalty, righteousness and fidelity…you will never obtain such courage.
I hope these principles have been a great insight into the life and mind of the ninja! We can utilize many of these ideas in our own lives as well, such as achieving courage and having a present and clear mind.