Epistemology
Types of Knowledge
Knowing-that, knowing-how, knowing-what — different epistemological categories
Philosophers distinguish different types of knowledge. (1) Propositional (knowing-that): facts. "I know that Paris is the capital of France." (2) Procedural (knowing-how): skills. "I know how to ride a bike." (3) Acquaintance (knowing-of): direct experience. "I know my mother." Other distinctions: a priori (independent of experience, e.g., math) vs a posteriori (from experience). Tacit vs explicit. Knowledge as power (Bacon). Each type has different epistemology — how acquired, how justified. Relations between types: debated. Some claim knowing-how reducible to knowing-that; others insist on separate category.
- PropositionalKnowing-that (facts)
- ProceduralKnowing-how (skills)
- AcquaintanceKnowing-of (direct experience)
- A prioriIndependent of experience (e.g., math)
- A posterioriFrom experience (e.g., empirical claims)
- DistinctionRyle's "Concept of Mind" (1949)
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Why knowledge types matter
- Epistemology. Foundation of theory of knowledge.
- Education. Different teaching methods.
- AI. Different problems for different types.
- Skill development. Practice vs study.
- Expertise. Tacit knowledge in fields.
- Cognitive science. Different mental processes.
- Philosophy of language. What "know" means.
Common misconceptions
- One kind of knowledge. Multiple types.
- All reducible to facts. Skills not just facts.
- Knowledge = belief. Knowledge requires justification, truth.
- Just propositional. Procedural, acquaintance also.
- Tacit unimportant. Critical for expertise.
- A priori means innate. Independent of experience; not necessarily innate.
Frequently asked questions
What's propositional knowledge?
Knowing-that. Knowledge that some statement is true. "I know that grass is green." Object: proposition (statement). Standard analysis: justified true belief (challenged by Gettier). Most philosophical attention to this type. Subject of epistemology debates: skepticism, foundationalism vs coherentism, etc.
What's procedural knowledge?
Knowing-how. Skill or ability. "I know how to ride a bike, swim, speak English." Different from propositional. You can know how to swim without explicit propositional knowledge of swimming. Conversely: knowing all swimming theory doesn't make you swim. Ryle (1949) emphasized this distinction. Implication: not all knowledge is propositional.
What's acquaintance?
Direct knowledge of person, place, or thing. "I know Paris" (been there). Different from "I know that Paris is in France" (propositional) and "I know how to navigate Paris" (procedural). Russell distinguished it. Empiricist tradition emphasizes: foundational knowledge is acquaintance with sense data.
What's a priori vs a posteriori?
Different epistemic source. A priori: knowledge independent of experience. Examples: 2+2=4, all bachelors are unmarried, geometry. Pure reason can establish. A posteriori: knowledge from experience. "Water boils at 100°C," "Trees are green." Empirical observation needed. Different philosophers disagree on what's a priori (Kant: math; Quine: nothing strictly a priori).
Is knowing-how reducible to knowing-that?
Important debate. Intellectualists (Stanley, Williamson): knowing-how is form of knowing-that. To know how to swim is to know certain propositions (about how swimming is done). Anti-intellectualists (Ryle): no — there are facts about how that aren't propositional. Athletes don't propositionally compute movements. Ongoing debate.
What's tacit knowledge?
Michael Polanyi's distinction. Knowledge difficult to articulate explicitly. Examples: riding bike (can do; hard to fully explain), face recognition, expert intuitions. Different from explicit knowledge (textbook facts). Important: skill, tradition, embodied expertise. Often: best learned through practice, not theory.
What's the difference between belief and knowledge?
Belief is mental state of accepting something. Knowledge requires more. Traditional: knowledge is justified true belief. Gettier showed JTB insufficient. Anyway: knowledge implies belief but not vice versa. False beliefs aren't knowledge. Belief unjustified isn't knowledge. Some beliefs may be true but accidental — also not knowledge (Gettier).