4 Groups of People

There are 4 groups of people,
Those who don't know that they don't know. These people are not worth teaching.

Those who know that they don't know. These people are willing to learn.

Those who don't know that they know. These people are unpolished gems. Teach them.

Those who know that they know. These people are teachers. Learn from them.

- Confucius

I heard this from my lecturer while delivering his talk at the hospital. It may be slightly different from the real quote but this was what I can remember from my fading memory box. The meanings are similar though no doubt about that.