I loved loopz's answer, but it's also important to grapple with the fact that you can never truly know whether a teacher is good. The path is always a risk. It's best to learn as much as you can and assess for yourself as you go.
In any event, the common wisdom is "you'll know." Or to put it plainly, do you like the person and feel like they have something to teach you?
I like the term "spiritual friend," because it's easy to understand the dynamic by analogy. How do you know one of your friends is truly your friend?
As for how many there are: I don't know. I live in the Bay Area, where the concentration of practitioners is perhaps highest in the US, and I'm aware of maybe a handful of teachers I would consider consider studying with. I'm aware of many more I would not.
Re:Anxiety is in your body, not your mind
by thanatos519 on Monday April 12, 2021 @03:46AM
(#26776900)
I like the term "dangerous friend": https://www.shambhala.com/dangerous-friend-466.html
You will notice you have lots to learn and experience that gives you something. No teacher is forever, except life itself perhaps.
It has more to do with the "student".
How many teachers actually have this, and how can one know that the one you’ve chosen is one of them?