The philosophical papers collected together in this volume cover a variety of topics centering around the three items of the title. Mereology, the theory of part-whole, appears and reappears throughout as a kind of basso ostinato for much that is said. For its full effect, however, mereology must be combined with various items treated in metalogic or logical semiotics, the modern trivium of syntax, semantics, and pragmatics. When pressed for their total philosophic richness, all of these subjects flow over into topics of perennial interest in metaphysics, including even metaphysical theology. It is thought that the treatment here brings these various subjects together in a new light and in an exact way. As a result, they are seen to gain in richness, scope, and depth, and a basis provided for the study of how intimately they interanimate each other. Each paper here is a critical and/or constructive adventure of ideas, not necessarily agreeing in all details with every other. Even though they are concerned with a considerable variety of philosophical topics, there is nonetheless a common methodology throughout, namely, the logica utens of first order quantification theory - or its algebraic surrogate - together with the first-order metalogic based on it, which are thought to provide the bedrock of sound philosophical method. This view has been spelled out in considerable detail in the author's previous publications and is further develop here in important ways. Richard M. Martin's work display a wealth of ideas, proposals, and formal analyses, always on top of the ideal of precision and rigour which were so important to him Lingua e Stile, 1988 Of interest to: Philosophers, linguists, logicians