the mind > mental capacity > knowledge > want of knowledge, ignorance > want of learning, illiteracy > be illiterate [verb] (2)
Phrases relating to the letter. not to know a B from a bull's foot, not to know a B from a battle-dore: to be entirely illiterate.
Phrases relating to the letter. not to know a B from a bull's foot, not to know a B from a battle-dore: to be entirely illiterate.