What I mean is that it is empty of any concept of itself. Let us distinguish between mind and consciousness. I think when you say 'mind', you really mean 'consciousness'. Mind is the faculty of thought, and as such, creates a self-concept of mind. Mind, IOW, is a self-created principle. It is only brought into being when thought is present. But consciousness does not involve thought. Consciousness is Pure Being, not existence in Time or Space, as Mind is. So yes, as Patanjali tells us: 'yoga [divine union] is the cessation of all of the activities of the mind'. No-mind is, in essence, pure consciousness, without thought; without concept; without self-nature, which is Sunyata.