Full Idea
Much of our propositional knowledge is not easily formulable, as when a witness looking at a police lineup may know what the culprit's face looks like.
Gist of Idea
Much propositional knowledge cannot be formulated, as in recognising a face
Source
Ernest Sosa (Beyond internal Foundations to external Virtues [2003], 6.1)
Book Reference
Bonjour,L/Sosa,E: 'Epistemic Justification' [Blackwells 2003], p.99
A Reaction
This is actually a very helpful defence of foundationalism, because it shows that we will accept perceptual experiences as knowledge when they are not expressed as explicit propositions. Davidson (Idea 8801), for example, must deal with this difficulty.
Related Idea
Idea 8801 Coherent justification says only beliefs can be reasons for holding other beliefs [Davidson]