Card 2.2 · Root II — Epistemology
Sources of Knowledge
Which ways of finding things out actually work?
This node asks where knowledge comes from — which channels can deliver it, and whether any of them is more basic than the rest.
Where it sits
Under II. Epistemology. Contains 2.2.1 Perception, 2.2.2 Reason and intuition, 2.2.3 Memory, 2.2.4 Testimony, 2.2.5 Revelation.
Narrower questions under this one:
- 2.2.1 Perception When you see a tree, what are you actually seeing?
- 2.2.2 Reason and Intuition How, if at all, do you know that a surface cannot be wholly red and wholly green at the same time and in the same respect?
- 2.2.3 Memory Is remembering a kind of perceiving, or a kind of imagining?
- 2.2.4 Testimony Do you need a reason to trust, or a reason not to?
- 2.2.5 Revelation Can something be known because it was disclosed rather than discovered?
The rival answers
| Position | Which sources count |
|---|---|
| Empiricism (strict form) | Sense experience only; everything else derives from it |
| Empiricism | Experience primary; reason arranges what it supplies |
| Kantian synthesis | Experience supplies content, the mind supplies structure; neither alone suffices |
| Rationalism | Reason primary; some substantive knowledge comes from reason independently of experience |
| Innatism | Some knowledge is present prior to any experience |
| Carvaka | Perception alone; inference and testimony rejected as independent sources |
| Buddhist (Dignāga) | Two: perception and inference. Testimony reduces to one of these |
| Nyaya | Four: perception, inference, comparison, testimony — each irreducible |
| Mimamsa | Bhāṭṭa: six — the above plus postulation and non-apprehension; Prābhākara: five, without non-apprehension |
Key figures
| Figure | Dates | Tradition | Contribution |
|---|---|---|---|
| Ajita Kesakambali | contemporary of the Buddha | Indian materialist | An early materialist stance, before the Lokāyata schools, known only through Buddhist and Jain reports |
| Gautama (Akṣapāda) | trad. c. 2nd c. CE | Indian Nyaya | The four-pramana framework |
| Dignāga | c. 480–540 | Indian Buddhist | Reduced the list to two and defended the reduction |
| Ibn al-Haytham | c. 965–1040 | Islamic | Experiment as a disciplined source |
| John Locke | 1632–1704 | European modern | No innate ideas; the mind begins empty |
| Immanuel Kant | 1724–1804 | European modern | Thoughts without content are empty, intuitions without concepts are blind (A51/B75) |
| Dharmakīrti | c. 6th–7th c. CE | Indian Buddhist | Only perception and inference are sources of knowledge, both grounded in causal efficacy |
| Suhrawardi | 1154–1191 | Islamic | Knowledge by presence (ʿilm ḥuḍūrī): self-knowledge needs no representation |
Connections
→ 2.1, 2.2.1, 2.2.4 · ↔ 2.3, 2.7, 2.2.5, 6.8 · ◇ empiricism, rationalism, Kantian synthesis, innatism, pramana pluralism · ○ Axial Age; Classical; Early modern; Table 3
→ narrower questions · ↔ questions it borders · ◇ the positions, mapped in Part III of the book · ○ the eras and comparison tables (Parts IV and V)
The full card is in the book
In The Coordinates of Thought this card goes on to a worked example that sets the answers against one case, and to where the question touches daily life — page 90.
On Coordinates of Thought
Conversations about this question in Reason & experience:
- Locke was right that the mind starts without ideas, and the argument from the newborn’s hunger fails 6 replies
- The self-defeat charge against the Cārvākas attacks a position they probably did not hold 6 replies
- Kant was wrong: we can know things as they are in themselves 5 replies
- Wang Yangming stared at bamboo for seven days and fell ill. Was he refuting empiricism? 5 replies
- The Cartesian circle: can clear and distinct perception vouch for itself? 5 replies