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Summary notes for What is knowledge?

The distinction between acquaintance knowledge, ability knowledge and propositional knowledge.

Ability: knowledge ‘how’ – e.g. “I know how to swim”
Acquaintance: knowledge ‘of’ some person, place or thing through direct awareness – e.g. “I know London”. Knowing what it is like to have this direct awareness.
Propositional: knowledge ‘that’ – e.g. “I know that London is the capital of England”
Epistemologists are mainly concerned with propositional knowledge because it is the type which can be represented in language and communicated.
The reason for the distinction is that there seem to be types of knowledge other than propositional. E.g. it’s not possible to reduce knowledge of how to swim to propositions. A person can’t be taught how to swim through learning facts. Nonetheless, it seems to make sense to say that some people know how to swim. So, there must be more types of knowledge than merely propositional.

The nature of definition (including Linda Zagzebski).

Epistemology has to start with a definition of knowledge, which raises the question of what a definition is and how it functions.
Zagzebski explains that epistemologists seek what is called a ‘theoretical definition’. This is is opposed to a practical definition, meaning a common-sense ordinary way that a word might be used by the average person. Not attempting to have precise theoretical clarity.
A theoretical definition attempts clarity through providing a necessary truth for what a thing must be.
A necessary truth is one that must be true. A theoretical definition will thus provide a necessary truth for what knowledge must be. It will explain what must be the case in order for knowledge to be held. This will remove any ambiguity, since either the conditions are present and so knowledge is held, or they aren’t and knowledge isn’t held.
This is achieved through necessary and sufficient conditions. E.g. ‘a batchelor is an unmarried man’ is a theoretical definition because it has precise necessary and sufficient conditions. Being unmarried is a necessary condition but not sufficient. Being unmarried and being a man are the necessary and sufficient conditions for being a batchelor.
Epistemologists want to find the conditions which are necessary and sufficient for knowledge since they will have then found the necessary truth for what must obtain in order to have knowledge, and thus a theoretical definition of knowledge.
Zagzebski also claims that theoretical definitions can be either real or conceptual. A real definition defines something with reference to an essential property in the world. E.g. ‘water is H2O’. An conceptual definition is when something socially constructed is defined, e.g. ‘A bachelor is an unmarried man’. Zagzebski says that we don’t know whether knowledge will have a real or conceptual definition until we successfully define it.

How propositional knowledge may be analysed/defined

Epistemologists argue that we can analyse or test the success of theoretical definitions of knowledge through truth condition analysis. This involves proposing necessary and sufficient conditions for knowledge which are then tested through trying to think of counter-examples.
E.g. JTB is tested through trying to think of examples of knowledge without one of the conditions (testing the individual necessity of JTB) or cases where the conditions are present and yet knowledge is not (testing the joint sufficiency of JTB).
Zagzebski argues that even if we could think of a definition which no one can think of counterexamples to, that could just be because we lack imagination. After all, Plato’s definition of knowledge was accepted for 2500 years until Gettier wrote his paper. So, Zagzebski says we can’t ever really be absolutely certain of a definition of knowledge since our only method for analysing or testing it depends on our ability to think of counterexamples.