Levels.
Truth is like vacuum. Absolute truth is not achievable and the closer to absolute - the more complex and deadlier. So only levels of truth approximation are the practical reality.
![](https://img-fotki.yandex.ru/get/876523/857191.5d/0_eecfb_3f7032db_XL.jpg)
Relationships.
One of the things about them is that some are subconsciously seeking thrills of changes rather than the peace of establishing them - ups and downs by definition produce more adrenalinary agitation vs boring plateaus. This is something they would even hide from themselves to a deep corner of consciousness.