Transposed language of norms

Author

The language of modalities is … a “transposed” language of norms. … Modal terms, normative terms and psychological terms are mutually irreducible. … The “means” of semantical statements…is no more a psychological word than is the “ought” of ethical statements or the “must” of modal statements

— Inference and Meaning Section 5

• Related to this quote.
• What is the connection between the (alethic) modal sense of must and the normative sense of must?
• Carnap uses ‘transposed’ to talk about an unquoted word used in a sentence as a transposed mode of speech (about use of a quoted-word).
  • Examples:
    • “Red is a quality.” vs “‘Red’ is a one-place predicate.”
    • “All $A$’s are necessarily $B$’s”. vs the license to infer $B$ statements from $A$ statements.