(Latin, of a thing/of a statement)
A contrast between two ways of interpreting sentences that may, or may not, be about a particular thing. Quine's example is ‘I want a sloop’, which may mean that there is a particular sloop I want, or which on the other hand may be true although I have no particular sloop in mind, when it just signals the desire for ‘relief from slooplessness’. The contrast can be given in the predicate calculus as that between: (∃x)(x is a sloop & I want to own x) and ‘I want it that: (∃x)(x is a sloop & I own x)’. The former can only be true if I am related to a specific thing, whereas the latter apparently relates me only to a statement, which I wish would become true but which could be made true by different things. Many contexts invite this ambiguity: ‘Jane said that the smallest girl in the class was taller than one of the others’ would impute a contradiction to Jane taken de dicto, but leaves her rationality unchallenged taken de re. Russell's example was the conversation: ‘I expected the ship to be longer than it is’; ‘No, it is just as long as it is.’ Knowledge de re is knowledge of a particular thing, that it is thus and so; knowledge de dicto is knowledge that something is the case where what is known could in principle be ‘realized’ by different things.