Shibboleth’s authenticate group membership based on knowledge. If you know the secret handshake, you’re one of us.
Nature Shibboleth’s authenticate group membership based on ability. If you can fly a plane, you’re one of us.
How does this still work to maintain group exclusivity? Because Things have an essential nature. You can’t really fake your way past these tests. Changing your nature to the point that you can pass just means that you now belong.
Many country clubs and golf courses are horribly expensive mainly to act as a barrier to entry. The group is exclusive to rich people, and so the only way you can get in is by being rich. If you have the ability to pay for entry, then you’ve proved you belong.
Being a lawyer is an exclusive club, but it isn’t a secret how to join - just pass a test. Of course, in doing so, you really have to become a lawyer. The ‘password’ for practicing law is your capability to practice law.
This is a natural counter to Imposter Syndrome - the mere fact that you can act in a way that passed the check is all that’s needed to authenticate you as someone who should be here.
If you passed the bar, you’re a lawyer - because the definition of a lawyer is someone who can pass the bar.