Writing like this means one must more than understand - must have kind of inner experience about these "things".

As I "understand" - there are two ways to perceive:

1. Subject - object understanding (subject has some understanding about the object which is distanced from the subject)

2. Becoming one with the "object" - you experience it, which means transcending dualistic way of perception.

The first is normal for humans but not so normal in Universe. This is perhaps one of the reason we can't find life outside of Earth.