Russell’s Theory of Descriptions

Bertrand Russell claimed that the reference of an expression is its meaning. At first he thought that the meaning of a definite description, for example "the present king of France," was some particular object, in this case a particular king. But at that time France had no king, so Russell thought that the king must exist in some way, even though he couldn't be found in our world. Soon enough, Russell came to think that this was too much ontology to swallow and proposed his theory of descriptions to avoid this consequence, while holding onto the idea that reference is meaning. His idea is that "the present king of France" doesn't have a meaning on its own, but any sentence in which this phrase occurs can be translated into a sentence in which the phrase doesn't occur.

"The present king of France is bald" is translated into "There is one and only one present king of France, and he is bald." If this is correct, then the original sentence with the definite description is false. Russell said that the second sentence revealed the logical form of the first sentence. Since the phrase "the present king of France" doesn't occur in this sentence there is no need for a particular king to exist for the sentence to have meaning.

Remember: The logical form of the statement: "The present king of France is bald" is given by "There is one and only one king of France, and he is bald."

Additionally: Underlying Russell's theory is the idea that a sentence has a "logical form" that makes its meaning and its logic easily understood. This idea was very influential on subsequent philosophers and linguists, including Ludwig Wittgenstein and Noam Chomsky.

source:
30-Second Philosophies by Barry Loewer