  Peirce’s settled opinion was that logic in the broadest sense is to be equated with semeiotic (the general theory of signs), and that logic in a much narrower sense (which he typically called “logical critic”) is one of three major divisions or parts of semeiotic. Thus, in his later writings, he divided semeiotic into speculative grammar, logical critic, and speculative rhetoric (also called “methodeutic”). Peirce’s word “speculative” is his Latinate version of the Greek-derived word “theoretical,” and should be understood to mean exactly what the word “theoretical” means.  Peirce’s tripartite division of semeiotic is not to be confused with Charles W. Morris’s division: syntax, semantics, and pragmatics (although there may be some commonalities in the two trichotomies).