what happens when someone refuses to accept a promotion to a higher rank in JuJitsu?

If you wait for that exact moment it would be disrespectful for you to refuse it in front of your teacher's invited guests. If you are not interested, tell your teacher waaaay ahead of time and if he insists, you should not push the issue further.

If he did not think you were ready, he would not consider you for promotion. He still may be offended that you don't trust his judgment.

When I did issue rank, I never tested anyone. I would just have the class in formation and speak about accomplishment, gaining knowledge and skill, and things like that, then call the person up to promote him/her. Then I would advise the underbelts that this person is to be looked at as someone who they can trust to give them guidance on issues up to their current rank.

Have a quick gang-up, just for fun and congratulate him/her, warning about how much harder it gets.

Sometimes I might do it in the middle of the class, other times in the beginning.

There is no need for you to refuse your rank.

Edit:

I just noticed Master Pugpaws' answer after I submitted mine... notice how they are almost identical in idea. He, being much more Senior to me over-shadows my 35 years... take heed of the voices of experiences.

Talking to your sensei about how you feel regarding formal ranks would be acceptable; but refusing outright is disrespectful.

Being obsessed about rank, regarding high ranks as absolute proof of skill, and focusing too much on your belt color will get you nowhere; but the rank system itself isn't harmful per se. The whole hierarchical system within martial arts (when implemented correctly) is actually a good benchmark of the overall progress of both the individual practitioner and the dojo as a whole. It also helps with overall training: the instructor can easily determine who needs to practice what (especially in larger dojos), junior members can easily be partnered up with more experienced students when necessary, etc.

Take the concept of black belts for example. Martial artists who think of it as a mark of mastery and dojos that promote getting a black belt as the ultimate goal has no business practicing martial arts. However, in a dojo where black belt holders are regarded properly - that is, having a good grasp of the basics - the instructor can then assume that these black belters are familiar with the basics and can be expected to move on to a more demanding training regimen with an added focus on the intricacies of the art. As a result, the overall training process becomes more effective.

IMHO, taking formal ranks too seriously is stupid, but disregarding its place in classical martial arts training is an act of ignorance. So, why don't you just take it easy, puts some faith in your instructors, and accept your promotion in the spirit in which it was offered: an acknowledgment of your hard work.

Yes, it would be a little offensive.

If the color of the belts mean nothing to you, then why would accepting promotion bother you? Do it because NOT doing it might cause a fuss. Do it because your instructor is probably proud of you, and wants to let others know you've progressed.

The only way you should refuse promotion is if you truly feel you haven't mastered the skills of the new level, in which case you should talk to your instructor about how you feel BEFORE publicly refusing the belt.

Traditionally it would be very rude. It is like saying that you know better than you Sensei when you deserve something. That being said, it also depends on the Sensei. I would not be offended by a student that approached me "Before" the rank test to tell me of their feelings on this subject. If you ask to talk to your instructor and are careful to be respectful yet truthful in telling him how you feel, you should have no problem. After doing this, if your instructor still wants you to test, then you should do so. I assume that you respect him and his judgment. If so then do what he says without question. Otherwise you should not be there in the first place. This should work out OK if you just talk to him before the rank test.

Best of Luck!

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