I just had a talk with a collegue yesterday that included the concept of self knowledge. In this case it was person who seemed not to be aware of how he was perceived by people around him. This made me think of a model that I presented to a client last week.
It is called Johari Window and has some great perspectives on self knowledge. This can be a concept that is hard to grasp at times, especially the interaction between others and yourself in the discovery of more of who you truly are.
If you are not familiar with this model I suggest a visit to the link above to see it illustrated. It basically speaks of one part of the window which contains what we know about our selfs and that others do to. Common knowledge about your personality that is.
There is also the hidden field, knowledge about your personality that you intentionally or unintentionally hide from others. Further theres is the blind field, things that other perceive about you, but that you are not aware of. A lot of times this can be for example how your body language comes across. This was field that was appropriate for the discussion initially mentioned in regards to self knowledge. Feedback would have been useful in that case to open up some of blind field would be my guess.
The last and fourth part of the window is the unknown. Unknown to you and others. Can be accessed via personality tests, therapy and the like.
The Leadership Briefing 