A little over a month ago, I recommended watching a video by Maitre A. A. Crown concerning one key thing that classical fencing teaches. For those of you who did watch it, you will know that the key thing being taught is, in a word, integrity. This should not be a foreign concept for any student of any traditional martial art, but especially for students in the International Taekwon-Do Federation (ITF) styles, it is one of the five central tenets of tae kwon do as taught by General Choi Hong Hi (General H. H. Choi)—courtesy, integrity, perseverance, self-control, and indomitable spirit.
Recognising that all of the tenets are important, I have often remarked to my senior students that, out of those five tenets, I personally consider that integrity should be listed first. To me, it is clear that without integrity, the rest are of limited value. (What good is it if someone is polite but dishonest? Diligent but self-serving? Indomitable but malevolent?)
Out of the five tenets, why did General Choi list courtesy first? I do not know; perhaps an answer lies in something that he has written or that he taught someone, but I just have not come across it yet.
For now, if I had to guess, I would suppose that it follows the principle that ‘karate begins and ends with courtesy.’ (Note that this is merely one loose translation from Japanese into English; there may be nuances that I am not aware of, since I do not speak Japanese.) That principle is the first of the twenty guiding principles of karate as set out by Master Funakoshi Gichin (Master G. Funakoshi), founder of what is now known as the Shotokan Karate style and, to many, the founder of modern karate overall.
Perhaps, in listing courtesy first, General Choi was showing martial respect to the art of karate that he had learned while living in Japan for a time.
I would consider both integrity and courtesy to be valuable tenets that younger people today should learn, that older people should model, and that all people (regardless of age) should practise as a matter of course. But if I had to choose one, it would have to be integrity, first and foremost.