In a recent note Bergmann states that “nonextensional languages may contain sentences from which contextually denned predicates are not eliminable.” A restatement of his argument is as follows. Suppose L is a functional calculus of fourth order. Included among the definitions occurring in L is

Let ϕ occur in A (where A represents a well-formed formula of L) without an argument. The elimination of ϕ from A in accordance with (1) requires

The proof of (2) depends on the principle of extensionality

Hence Bergmann's conclusion “no such general elimination rule can be constructed for nonextensional languages.”