PERSON AND OBJECT by Roderick M. Chisholm. U.K.: Allen & Unwin; U.S.A.: Humanities Press, 1976. 230 pp. £7.25.

Achieving space situational awareness requires, at a minimum, the identification, characterization, and tracking of space objects. Leveraging the resultant space object data for purposes such as hostile threat assessment, object identification, and conjunction assessment presents major challenges. This is in part because in characterizing space objects we reference a variety of identifiers, components, subsystems, capabilities, vulnerabilities, origins, missions, orbital elements, patterns of life, operational processes, operational statuses, and so forth, which tend to be defined in highly heterogeneous and sometimes inconsistent (...) ways. The Space Domain Ontologies are designed to provide a consensus-based realist framework for formulating such characterizations in a way that is both consistent and computable. Space object data are aligned with classes and relations in a suite of ontologies built around the existing Space Object Ontology. They are stored in a dynamically updated Resource Description Framework triple store, which can be queried to support space situational awareness and the needs of spacecraft operators and analysts. This paper provides an overview of the Space Domain Ontologies and their development and use. It presents the motivation for and advantages of the Space Domain Ontologies, including the benefits they provide for enhancing and maintaining long-term space situational awareness. (shrink)

Although the theory of definability had many important antecedents—such as the descriptive set theory initiated by the French semi-intuitionists in the early 1900s—the main ideas were first laid out in precise mathematical terms by Alfred Tarski beginning in 1929. We review here the basic notions of languages, explicit definability, and grammatical complexity, and emphasize common themes in the theories of definability for four important languages underlying, respectively, descriptive set theory, recursive function theory, classical pure logic, and finite-universe logic. We review (...) the history of previous studies of the similarities and differences in the theories of definability of the first three of these four languages. A seminal role leading toward unification of the theories has been played by the separation principles introduced by Nikolai Luzin in 1927. Emphasizing analogies and driving toward further unification embracing finite-universe logic we concentrate on a simple example—the first and second separation principles for existential-universal first-order sentences . Using this as a test case for the fundamental problem of how to “finitize” arguments in classical pure logic to the finite-universe case, we are led to the analogous negative solution by using the theory of certain special graphs: a graph is - special for any positive integers m , n , p , q iff it is bipartite with m red points and n blue points and for every p -tuple of red points there is a blue point to which they are all connected . As an aside we introduce for further study a natural “Ramseyesque” increasing sequence A of positive integers, where A is the least positive integer n for which an -special graph exists. (shrink)

Recently a growing number of biologists have begun to consider the causal role that processes of embryonic development may play in evolution. This constitutes a reunion of these phenomena which had been linked in the nineteenth century through Haeckel's biogenetic law. This reunion may result in a new subdiscipline of biology, if there is a set of unique concepts and methods which tie the various research approaches together. Such concepts as bauplan, canalization, and developmental constraint, may serve in such a (...) capacity. The methods employed must combine comparative and experimental analyses, with special attention paid to the range of variation in developmental events within each taxon. These concepts and methods are also applicable to the problem of how development evolved, thus the evolution of development may also be considered part of the reunion. The reunion is discussed in terms of the potential participation of various schools of thought found in the current literature. (shrink)

The purpose of this brief introduction is to describe the origin of the papers here presented and to acknowledge the help of some of the many individuals who were involved in the preparation of this volume. Of the eighteen papers, nine stem from the annual fall colloquium of the Depart ment of Philosophy at the University of Western Ontario held in London, Ontario from November 10 to November 12, 1967. The colloquium was entitled 'Philosophical Logic'. After some discussion, the editors (...) decided to retain that title for this volume. Von Wright's paper 'On the Logic and Ontology of Norms' is printed here after some revision. A. R. Anderson commented on the paper at the colloquium, but his comments here are based upon the revised version of the von Wright paper. The chairman of the session at which von Wright's paper was read and discussed was T. A. Goudge. Aqvist's paper 'Scattered Topics in Interrogative Logic', and Belnap's comments, 'Aqvist's Cor rections-Accumulating Question-Sequences', are printed as delivered. The chairman of the Aqvist-Belnap session was R. E. Butts. Wilfrid Sellars' paper 'Some Problems about Belief' is printed as delivered at the col loquium, but 'Quantifiers, Beliefs, and Sellars' by Ernest Sosa is a revision of his comments at the colloquium. That session was chaired by G. D. W. Berry. Ackermann's paper 'Some Problems oflnductive Logic', as well as Skyrms' comments, are printed as delivered. (shrink)