It has been argued that Psychological Externalism is irrelevant to psychology. The grounds for this are that PE fails to individuate intentional states in accord with causal power, and that psychology is primarily interested in the causal roles of psychological states. It is also claimed that one can individuate psychological states via their syntactic structure in some internal "language of thought". This syntactic structure is an internal feature of psychological states and thus provides a key to their causal powers. I argue that in fact any syntactic structure deserving the name will require an external individuation no less than the semantic features of psychological states