I don't think OP needs to prove that just yet. This is more of an invitation to pitch/brainstorm ideas. Imagine asking everyone who wants to potentially invest to verify their balances beforehand. It's not necessary until something materialistic formulates.
This is the same reason I have asked OP for a singed message. Have a look on few posts above, I do not think there are some people who are giving brainstorming idea. Me personally will not even bother to drop a message here with any idea. These place is noisy, I mean very noisy. Tomorrow someone else will come and say they have 50BTC and looking for idea. If I was seriously looking for idea then I would not simply drop a message like this...
Hi
I have 24 BTC, i bought 7 btc about 5 years ago and raise up it with trade and primedice.
I want to start a BTC Project with 20 btc, if do you have an BTC idea project, please tell me.
We can corporate together for do it.
You must have expertise in the field of the project.
Thanks
They would put some thoughts, their previous background, experience, skills etc if the person was really serious about ideas.
Based on what you want to give him idea?
If the person is a plumber but you end up giving him an idea about how to build AI robots do you think s/he will understand your idea?