"Stance in Strategy Adopt a stance with the head erect, neither hanging down, nor looking up, nor twisted. Your forehead and the space between your eyes should not be wrinkled. Do not roll your eyes nor allow them to blink, but slightly narrow them. With your features composed, keep the line of your nose straight with a feeling of slightly flaring your nostrils. Hold the line of the rear of the neck straight: instill vigor into your hairline, and in the same way from the shoulders down through your entire body. Lower both shoulders and, without the buttocks jutting out, put strength into your legs from the knees to the tips of your toes. Brace your abdomen so that you do not bend at the hips. Wedge your companion sword in your belt against your abdomen, so that your belt is not slack - this is called "wedging in"."
Japanese swordsman, philosopher, strategist, writer, artist, and rōnin (1584–1645)
Miyamoto Musashi 宮本 武蔵 (c. 1584 – 13 June 1645) was a famous Japanese swordsman, believed to have been one of the most skilled swordsmen in history. He founded the Hyoho Niten Ichi-ryu, or Nito Ryu style of swordsmanship and wrote Go Rin No Sho (The Book of Five Rings) a classic work on strategy, tactics, and philosophy.
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When we are fighting with the enemy, even when it can be seen that we can win on the surface with the benefit of the Way, if his spirit is not extinguished, he may be beaten superficially yet undefeated in spirit deep inside. With this principle of "penetrating the depths" we can destroy the enemy's spirit in its depths, demoralizing him by quickly changing our spirit. This often occurs. Penetrating the depths means penetrating with the long sword, penetrating with the body, and penetrating with the spirit. This cannot be understood in a generalization. Once we have crushed the enemy in the depths, there is no need to remain spirited. But otherwise we must remain spirited. If the enemy remains spirited it is difficult to crush him.
when we are fighting with the enemy, and an entangled spirit arises where there is no possible resolution. We must abandon our efforts, think of the situation in a fresh spirit then win in the new rhythm. To renew, when we are deadlocked with the enemy, means that without changing our circumstance we change our spirit and win through a different technique
This book is a spiritual guide for the man who wishes to learn the Way.
My heart has been inclined to the Way of strategy from my youth onwards. I have devoted myself to training my hand, tempering my body, and attaining the many spiritual attitudes of sword fencing. If we watch men of other schools discussing theory, and concentrating on techniques with the hands, even though they seem skilful to watch, they have not the slightest true spirit.
Of course, men who study in this way think they are training the body and spirit, but it is an obstacle to the true Way, and its bad influence remains for ever.
When you and your opponent are fighting and nothing is going right, nor is there progress, be of a mind to throw off your former intention and start entirely anew. Take on another rhythm and see your way to victory. With Renewal, whenever you think that you and your opponent are just grating along, you should change your mind on the spot and take the victory by using another tactic.
This is what you’re looking for. In fact, The Book of Five Rings is often placed alongside The Art of War by Sun Tzu, On War by General Carl von Clausewitz, Infantry Attacks by Field Marshal Erwin Rommel, and Patterns of Conflict by Colonel John Boyd. Each of these works has materially influenced military thinking, directly or indirectly influencing modern combat despite the fact that they were written decades or even centuries ago.