Out of the nowhere of the dimensionless state comes the differentiation of the sound of the trumpet in the dimensional state, in the now here of the dimensional state. That sound is generated first in the mouthpiece of the trumpet, and the vibration is taken up by the air contained in the whole trumpet and by the trumpet itself. This portrayal indicates a oneness, first of all between the trumpeter and the trumpet; and then the oneness between the air (the substance in the trumpet), the trumpet itself, and the sound that is being propagated.

The Third Sacred School, Volume 2, Chapter 73