Are you an expert? Do you know an expert? Do you want to be an expert?
This came up for me the other day while having a discussion with a self proclaimed expert. I'm not going to claim I'm an expert at anything, but if you tell me all about how good you are, I'm not going to take it at face value. I'm going to demand some proof. "Trust me" isn't proof.
There are a rather large number of people who think they are experts, some think they're experts at everything. Nobody is an expert at everything. People who claim to have done everything should be looked at with great suspicion. Everyone can be an expert at something though.
One of the challenges we always face is trying to figure out who is actually an expert, and who only thinks they are an expert? There are plenty of people who sound very impressive, but if they have to deal with an actual expert, things fall apart pretty quick. They can get you into trouble if you're expecting expert advice. Especially in areas like security, bad advice can be worse than no advice.
The simple answer is to look at their public contributions. If you have someone who has ZERO public contributions, that's not an expert in anything. Even if you're working for a secretive organization, you're going to leave a footprint somewhere. No footprint means you should seriously question a person's expertise. Becoming an expert leaves a long crazy trail behind whoever gets there. In the new and exciting world of open source and social media there is no excuse for not being able to to show off your work (unless you don't have anything to show off of course).
If you think you're an expert, or you want to be an expert, start doing things in the open. Write code (if you don't have a github account, go get one). Write blog posts, answer questions, go to meetups. There are so many opportunities it's not even funny. Just because you think you're smart doesn't mean you are, go out and prove it.