I have asked this many times and have been given several different answers. So whilst being unable to train at the moment I have been doing some reading…

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The source page for this article is: http://www.shindai.com/

Mitsugi Saotome Sensei, “The Principles Of Aikido”

“When I was uchi deshi to O Sensei, everyone was required to wear a hakama for practice, beginning with the first time they stepped on the mat. There were no restrictions on the type of hakama you could wear then, so the dojo was a very colorful place. One saw hakama of all sorts, all colors and all qualities, from kendo hakama, to the striped hakama used in Japanese dance, to the costly silk hakama called sendai-hira. I imagine that some beginning student caught the devil for borrowing his grandfather’s expensive hakama, meant to be worn only for special occasions and ceremonies, and wearing out its knees in suwariwaza practice.

I vividly remember the day that I forgot my hakama. I was preparing to step on the mat for practice, wearing only my dogi, when O Sensei stopped me. “Where is your hakama?” he demanded sternly. “What makes you think you can receive your teacher’s instruction wearing nothing but your underwear? Have you no sense of propriety? You are obviously lacking the attitude and the etiquette necessary in one who pursues budo training. Go sit on the side and watch class!”

This was only the first of many scoldings I was to receive from O Sensei. However, my ignorance on this occasion prompted O Sensei to lecture his uchi deshi after class on the meaning of the hakama. He told us that the hakama was traditional garb for kobudo students and asked if any of us knew the reason for the seven pleats in the hakama.

“They symbolize the seven virtues of budo,” O Sensei said. “These are jin (benevolence), gi (honor or justice), rei (courtesy and etiquette), chi (wisdom, intelligence), shin (sincerity), chu (loyalty), and koh (piety). We find these qualities in the distinguished samurai of the past. The hakama prompts us to reflect on the nature of true bushido. Wearing it symbolizes traditions that have been passed down to us from generation to generation. Aikido is born of the bushido spirit of Japan, and in our practice we must strive to polish the seven traditional virtues.”