  Kaplan (1989a, p. 505) says that he represents the character of an expression with a function on contexts whose value at any context is the expression’s content at that context. For example, the content of ‘I’ at any context \(c\) is the agent character of \(c\). So the character of ‘I’ is a function on contexts whose value at any context \(c\) is the agent of \(c\). The value of the character of ‘I’ at a context in which Mary is the agent is just Mary herself, and its value at a context in which John is the agent is just John himself. The character of a sentence is a function whose value at any context is the structured propositional content of that sentence at that context. For instance, the character of ‘I am a philosopher’ is a function whose value at any context \(c\) in which \(A\) is the agent of \(c\) is the proposition  \(\langle A, \text{being a philosopher} \rangle\).  If Mary is the agent of \(c\), then the value of this function at \(c\) is  \(\langle \text{Mary}, \text{being a philosopher} \rangle\).