(no subject)

18. In everything always observe what the thing is which produces for thee an appearance, and resolve it by dividing it into the formal, the material, the purpose, and the time within which it must end.

Marcus Aurelius. The Meditations, Book 12.
https://www.bartleby.com/lit-hub/hc/the-meditations-of-marcus-aurelius/xii-15

cf Aristotle's four causes: formal, material, final, efficient.