The reliable witness

From: A Trackless Path 13
Full transcript

Ken: Let's start with a simple question. How many of you have expectations about your practice? What it should be like and how you should be in the world as a result of this practice? Well, one of the more relieving and one of the more troubling instructions in The Great Path of Awakening is, Rely on the principal witness.  
And the commentary says, as you practice mind training, people may come to you and say, "Oh, you're a much nicer person than you used to be. You're much easier to get along with. You must be making great progress in your practice." And so you think, "Oh, I'm getting somewhere." But that's regarded in mind training as an unreliable witness because people don't know what's actually going on inside you. All they're doing is basing it on behavior. 
And this certainly has happened to me. In the first three-year retreat I got a note from my wife, who was in the women's retreat saying, "From what the other guys are saying you're making great progress in your practice because you're much easier to live with now." And this was further confirmed many years later when I was in Vancouver helping to establish a center there. I was visiting with some old friends, and we were chatting in the kitchen. She came up, put her arm around me and said, "I think I can say this now, Ken, you really were an asshole." [Laughter]  
So, what do you do with that? So that's the unreliable witness.  
And Kontrul goes on in his commentary to say...I'm going to experiment with getting rid of the word mind for awhile and see what that's like.
When you are clear inside and not experiencing regrets or shame about your actions, that's the reliable witness 
Student: Could you repeat that?

Ken: When you are clear inside and have no regrets or shame about your actions, that's the reliable witness. What he's saying is the reliable witness is mind itself.