Another important distinction between names and descriptions is that a name cannot occur significantly in a proposition unless there is something that it names, whereas a description is not subject to this limitation. ... The proposition 'the golden mountain does not exist' becomes 'the propositional function "x is golden and a mountain" is false for all values of x.' The statement 'Scott is the author of Waverley' becomes 'for all values of x, "x wrote Waverley" is equivalent to "x is Scott".' Here, the phrase 'the author of Waverley" no longer occurs.
Source: My Philosophical Development, chap. 7：1959．
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