One supposition underlying the Anderson & Lebiere target article is that the maximally broad “encompassing of its subject matter – the behavior of man” is regarded as an unquestioned quality criterion for guiding cognitive research. One might argue for an explicit specification of the limitations of a given paradigm, rather than extending it to apply to as many domains as possible.

One does not have to be an ethical non-cognitivist to find that moral guidance sometimes is totally absent. The agent may be confronted by a new kind of problem, or he may feel that the rules presented are too unclear to give any guidance, or he may quite simply regard established morality as without foundation. 1. Total ignorance; 2. Synthesis; 3. Towards solution; 4. Universal validity; 5; Ethical agnosticism.

Halldén completeness closely resembles the relevance property. To prove Halldén completeness in terms of Kripke-style semantics, the van Benthem–Humberstone theorem is often used. In relevant modal logics, the Halldén completeness of Meyer–Fuhrmann logics has been obtained using the van Benthem–Humberstone theorem. However, there remain a number of Halldén-incomplete relevant modal logics. This paper discusses the Halldén completeness of a wider class of relevant modal logics, namely, those with some Sahlqvist axioms.