Descriptive
The chain of reasons
On the axis: Justification of belief · the chain of reasons
Every belief rests on a reason, which rests on another: either the chain stops at beliefs that justify themselves, or it closes into a circle where each supports the others, or it runs off to infinity. These three exits are exactly the three ways of answering "what justifies a belief?".
Anchors: Sextus Empiricus · Aristotle