Justification is the property of a belief that is the key component of knowledge. Justification provides support for a belief:
Common sources of justification:
- sense perception
- logic
- memory
- testimony
Ayer-version-of-the-analysis-of-knowledge refines the meaning of justification in epistemology, and outlines the standard associated with the “right to be sure”.
Gettier salvages traditional-analysis-of-knowledge by requiring that justification for our belief must require true claims.
There are two possible ways justification is structured, which gives structure-of-knowledge.
Internalist and externalist theory of knowledge
internalist theories of knowledge maintains that for a belief to qualify as knowledge, the justificatory grounds must be internal (i.e. accessible) to the knower.
This means that in order to qualify as knowledge, the belief must be mentally accessible to states or conditions that justify the belief. E.g.
- for a perceptual belief, you need to be able to access the perceptions, or recover the perceptions from memory.
- for inferential knowledge, you need to be able to recover the justifying reasons that form the basis for the inference
internalist asks = what justification can you give for your belief? is it adequate?
externalist theories of knowledge maintains that at least some of the grounds of a belief’s qualifying as knowledge can be external to the knower.
Goldman’s theory of knowledge involves factors external to the knower, such as the objective causal connections that the knower does not need to be aware of.
externalist asks = does the belief hook up with the world in an appropriate way, even if the knower can’t give evidence or proof?
The externalist does not deny that there can be internal reasons that play some role in establishing relevant relationship with the facts. However, even when internal reasoning is involved, it’s how that process fits into the broader objective relationship between your belief and the fact.