Wu Te, Great Master of Ch'an said:

The mind of Ch'an is one in which
You and I are fully harmonious
The saints and the laymen are all uniform
All things are free to take their course
All things are being cherished

The mind of Ch'an is one in which we leave all marks behind. It is a mental state without the discriminating conceptions of self, others, living beings and life span as stated in the Diamond Sutra.