The six categories rely on different epistemic paths:
1. First principles — direct judgment from understood concepts.
2. Innate inferences — judgment through an immediately available middle.
3. Intuitions — immediate grasp of relevant principles.
4. Observations — external or internal perception.
5. Experiences — repeated relevant observation supporting a general rule.
6. Mass reports — sufficiently independent and convergent testimony.
Appropriate testing differs: locate the middle term in fiṭriyyāt, assess repetition and conditions in tajribiyyāt, and inspect reporting paths in mutawātirāt.