How do I know I have clear mind or not?



During a kong-an interview, the student was not sure how clear mind works. 

Student: What is clear mind? How do I know whether I have this clear mind or not.
Sifu: Clear mind is like a clear mirror. You use a mirror every day, right?
Student: Right, I do. But how does a mirror connect with clear mind.
Sifu: If you stand in front of a mirror alone, will you see your husband’s face in the mirror?
Student: Of course not, Sifu.
Sifu: That‘s clear mind like a clear mirror.

Commentary:
Diamond Sutra says, “Past mind cannot be attained. Present mind cannot be attained. Future mind cannot be attained.” If we use this teaching in our everyday life, that is clear mind.
The mirror’s job is to only reflect whatever appears in front of the mirror. It will not label the reflection. When our mind is clear, it is like a mirror. We can see everything as it is. 
Our practice doesn’t just stop there. We need to take one more step. How can we use this clear mirror mind to make correct life? When you are hungry, eat. When people are hungry, give them food. Our helping people with what they need is clear mind‘s job.