Discover published sets by community

Reference (Bedeutung) is the object to which a name or a term refers, while sense (Sinn) is the way the reference is presented. For instance, 'Morning Star' and 'Evening Star' both refer to the planet Venus (the reference) but have different senses.

The sense of a proposition is the thought it expresses. For instance, the sense of the proposition 'The sky is blue' is the concept or thought of the sky's color being blue.

The principle of compositionality, posited by Frege, is that the sense of a complex expression is determined by the senses of its parts and their mode of combination. For example, the meaning of a sentence is built from the meanings of its individual words and their syntactic arrangement.

Frege addressed the issue of empty names, which have no reference. For example, 'Sherlock Holmes' has a sense but no real-world referent.

Frege proposed that sentences have references, which are their truth values (True or False). Therefore, every declarative sentence refers to either the True or the False.

Frege's work laid groundwork for compositional semantics, arguing the meaning of an expression is determined by its structure and the meanings of its constituents. For example, the meaning of 'red apple' combines the senses of 'red' and 'apple' through adjective-noun composition.

In Frege's theory, information content relates to the sense of an expression, as different senses provide different information. For example, 'Venus' and 'Hesperus' both refer to the same planet but convey different information.

Frege's context principle states that the meaning of a word only becomes clear within the context of a proposition. For example, 'bank' can mean different things but we understand its meaning from the surrounding sentence.

Opaque contexts are linguistic contexts where substitutivity of identicals fails due to referential opacity. For example, in propositional attitude reports like 'Alice believes that Mark Twain wrote Huckleberry Finn,' substituting 'Mark Twain' with 'Samuel Clemens,' though they refer to the same person, may change the truth value.

Frege treated definite descriptions as expressions with both sense and reference. For example, 'the author of Huckleberry Finn' has a sense concerning the way we think about the author and refers to a specific individual, Mark Twain.

Frege believed that the reference of a predicate is a concept, which can be understood as a function that maps each argument to a truth value. For instance, the reference of the predicate 'is a philosopher' would be the function that assigns 'True' to individuals who are philosophers.

The principle of substitutivity of identicals states that if 'a' and 'b' are identical, then one can be substituted for the other without changing the truth value. However, Frege noted this doesn't always apply to sentences with different senses.

Frege differentiated existence from predication by assigning existence to second-level concepts. In his framework, 'Unicorns do not exist' states that the concept 'unicorn' fails to be instantiated, rather than predicating non-existence to some subject.

The sense of a sentence, for Frege, is its thought—a proposition that can be true or false. The thought is independent of the truth value itself. For example, 'Snow is white' and 'Schnee ist weiß' express the same thought in different languages.

Sense is associated with the cognitive value of an expression because it provides the means by which an individual can think about the referent. E.g., knowing someone as 'Clark Kent' versus 'Superman' involves different senses and thus different cognitive values.

According to Frege, the reference of a proper name is the entity it stands for. For example, the name 'Aristotle' refers to the ancient Greek philosopher.

Frege argues that identity statements such as 'a = b' have cognitive value only if 'a' and 'b' have different senses but the same reference. For example, 'The Morning Star is the Evening Star' conveys new knowledge despite both terms referring to Venus.

Indirect reference occurs when we talk about the sense rather than the reference itself, often in indirect discourse or under attitudes like belief. E.g., in 'Galileo thought the object of his observation was the planet Venus'.

Frege's Puzzle involves the cognitive significance of identity statements. It asks why 'a = a' seems trivial but 'a = b' can be informative if 'a' and 'b' refer to the same object, highlighting the difference between sense and reference.