Berit Brogaard

“When a speaker says something of the form A and B, he may take it for granted that A (or at least that his audience recognizes that he accepts that A) after he has said it. The proposition that A will be added to the background of common assumptions before the speaker asserts that B. Now suppose that B expresses a proposition that would, for some reason, be inappropriate to assert except in a context where A, or something entailed by A, is presupposed. Even if A is not presupposed initially, one may still assert A and B since by the time one gets to saying that B, the context has shifted, and it is by then presupposed that A” (Stalnaker 1974).

On an initially plausible view of ignorance, ignorance is equivalent to the lack or absence of knowledge-that. I argue that this view is incorrect, as lack of sufficient justification for one's true belief or lack of belief doesn't necessarily amount to ignorance. My argument rests on linguistic considerations of common uses of 'ignorant' and its cognates. The phrase 'is ignorant of', I argue, functions differently grammatically and semantically from the phrase 'does not know', when the latter is used propositionally. 'Is ignorant of' does not have a genuine propositional use but is best understood as equivalent to 'is not knowledgeable of'. I further argue that 'knowledgeable' and 'ignorant' are relative gradable expressions. Relative gradables typically are associated with an implicit or explicit standard of comparison, give rise to borderline cases and trigger the Sorites Paradox in their unmarked form. From these linguistic considerations, it follows that being ignorant admits of degree, and that one can fail to be ignorant despite lacking true beliefs concerning the propositions constituting a particular subject matter. The proposed treatment of knowledgeability and ignorance of facts and subject matters lends itself to an alternative reply to the problem of skepticism, which I will call the ‘simple response’. In the final section of the paper I argue that ignorance can also reflect incompetence with respect to a particular activity. The latter, I argue, is a case of lacking a particular kind of ability-involving knowledge-how, viz. practical knowledge of how to perform the activity in question.