Friends:

  Emergence of the Four Frames of Reference:
 

The Buddha once explained the profundity of causality like this:
Arising of Nutriment induces the emergence of the Body...
Ceasing of Nutriment induces the passing away of the Body...

Arising of Contact induces the emergence of Feeling...
Ceasing of
Contact induces the passing away of Feeling...

Arising of Naming-&-forming induces the emergence of Mind...
Ceasing of
Naming-&-forming induces the passing away of Mind...

Arising of Attention induces the emergence of Phenomena...
Ceasing of Attention induces the passing away of Phenomena...

Therefore is considering, contemplating, analyzing, and recollecting:
1: Body merely as a transient form grown up on food;
2: Feeling only as passing emotion arisen from sense-contact;
3: Mind just as changing mood emerged from
naming-&-forming;
4: Phenomena only as momentary mental states created by attention.
It is a crucial necessity to reflect on these 4 facts repeatedly, and thoroughly.
This is called initiating and developing the
Four_Foundations_of_Awareness,
which, in itself, is the mental treasure par excellence, that leads steadily,
and directly to the Deathless Element: Nibbāna...



More on these Four Foundations of Awareness (Satipatthāna):
What is Right Awareness?, Four_Foundations_of_Awareness,
Awareness_Sati,
Satipatthana, The_Awareness_Ability.

Source: The Grouped Sayings by the Buddha. Samyutta Nikāya V 184
http://store.pariyatti.org/Connected-Discourses-of-the-Buddha_p_1379.html
https://What-Buddha-Said.net/library/ati_website/html/tipitaka/sn/index.html

Causes of Emergence...