Day 13
The concept of universal oneness - that all things in their essential nature have no distinguishing characteristics - is called
Śūnyatā. Śūnyatā means non-substantiality, the un-born, having no self-nature, no duality. It is because things in themselves have no form or characteristics that we can speak of them as neither being born or being destroyed. There is nothing about the essential nature of all things that can be described in terms of discrimination; that is why things are called non-substantial.
All things appear and disappear because of the concurrence of causes and conditions. Nothing can ever exist entirely alone; rather, all things exist in relation to everything else.
Whenever there is a light, there is shadow; whenever there is length, there is shortness; whenever there is white, there is a black. Just like these examples, the essential nature of the things cannot exist alone and is hence non-substantial.
Day 14
Behind the desires and worldly passions which the mind entertains, there abides clear and undefiled, the fundamental and true essence of mind.
Water is round in a round receptacle and square in a square one, but water of itself has no particular shape. Most people remain unaware of this fact.
People are caught in the entanglements of discriminating between good and bad; choosing between things they like and dislike; find agreeable and disagreeable; and thinking whether things exist or do no exist. People become attached with this way of thinking and as a result, suffer.
If it were only possible for them to serve the attachments to these imaginary and false discrimination and restore the original purity of their minds, then their minds and bodies would become free of suffering and they would know the peacefulness that comes with that freedom.