“Heaven is eternal
Earth is ancient
The reason Heaven and Earth
Is because they do not exist for themselves
Thus are they able
To live forever”
That which has a self soon comes to an end. That which has no self never comes to an end. A self is defined by its limitations. What makes me appear to be different from you are my limiting factors: possessing one hair colour instead of another; being a particular height instead of another. What makes you appear to be different from me are your own limiting factors – your size, your smell, your shape, your concerns. In both cases, we are defined by what we are not – a cookie cutter imprinting our individuating boundaries.
What makes Heaven and earth different (as spiritual principles, rather than just physical realities) is that they are defined by their lack of attributes. Having no attributes, they embrace all attributes – this is the attributeless attribute. Having no selfhood, their consciousness is limited to being neither one thing nor another. Because their consciousness does not dwell in specific vessels, it is free to dwell everywhere. So selflessness is boundlessness. And boundlessness cannot end.