Online research in philosophy

We give complete sequent-like tableau systems for the modal logics KB, KDB, K5, and KD5. Analytic cut rules are used to obtain the completeness. Our systems have the analytic superformula property and can thus give a decision procedure. Using the systems, we prove the Craig interpolation lemma for the mentioned logics.

The implications of Globalization on education are multifaceted. However, roots of all these implications can be traced to the predominance of economic activity at the global level. The education and learning paradigm, around the world is under increasing pressure to meet the demands of the new knowledge and information-intensive global economy in a better way. This kind of pressure is challenging the traditional relationships between teachers and students and causing paradigm shifts in the process of learning. Especially, as noted by (...) KB Power (2002:i) ‘Higher education has undergone important paradigm shifts including the shift from teacher-centered to a student centered learning, and the replacement of the traditional practice of learning over a period of time by the concept of lifelong learning.’ Along with these there are major shifts in the modes of instructional technologies - from face to face oral instruction to print based instruction, and from Multimedia based videotapes and Television channels to E-learning systems. The present paper limits itself to the paradigm shifts in the concept of education with reference to learner. After a brief introduction on how education is understood in globalization the paper discusses the place of learner which is transforming according to the needs of global economy. (shrink)

The most prominent arguments for scepticism in modern epistemology employ closure principles of some kind. To begin my discussion of such arguments, consider Simple Knowledge Closure (SKC): (SKC) (Kxt[p] ∧ (p → q)) → Kxt[q].1 Assuming its truth for the time being, the sceptic can use (SKC) to reason from the two assumptions that, firstly, we don’t know ¬sh and that, secondly, op entails ¬sh to the conclusion that we don’t know op, where ‘op’ and ‘sh’ are shorthand for ‘ordinary (...) proposition’ and ‘sceptical hypothesis’ respectively. (SKC), however, fails for familiar reasons: since knowledge entails belief (KB), we can derive the falsity (F) from (SKC) by hypothetical syllogism, and thus reduce (SKC) to absurdity: (KB) Kxt[p] → Bxt[p]. (F) (Kxt[p] ∧ (p → q)) → Bxt[q]. (shrink)

We argue, contrary to epistemological orthodoxy, that knowledge is not purely epistemic -- that knowledge is not simply a matter of truth-related factors (evidence, reliability, etc.). We do this by arguing for a pragmatic condition on knowledge, KA: if a subject knows that p, then she is rational to act as if p. KA, together with fallibilism, entails that knowledge is not purely epistemic. We support KA by appealing tothe role of knowledge-citations in defending and criticizing actions, and by giving (...) a principled argument for KA, based on the inference rule KB: if a subject knows that A is the best thing she can do, she is rational to do A. In the second half of the paper, we consider and reject the two most promising objections to our ease for KA, one based on the Gricean notion of conversational implicature and the other based on a contextualist maneuver. (shrink)

We describe a KB Gödelian ontological system, and some other weak systems, in a fully formal way using theory of types and natural deduction, and present a completeness proof in its main and specific parts. We technically and philosophically analyze and comment on the systems (mainly with respect to the relativism of values) and include a sketch of some connected aspects of Gödel''s relation to Kant.

We have synthesized a 582,970-base pair Mycoplasma genitalium genome. This synthetic genome, named M. genitalium JCVI-1.0, contains all the genes of wild-type M. genitalium G37 except MG408, which was disrupted by an antibiotic marker to block pathogenicity and to allow for selection. To identify the genome as synthetic, we inserted "watermarks" at intergenic sites known to tolerate transposon insertions. Overlapping "cassettes" of 5 to 7 kilobases (kb), assembled from chemically synthesized oligonucleotides, were joined by in vitro recombination to produce intermediate (...) assemblies of approximately 24 kb, 72 kb ("1/8 genome"), and 144 kb ("1/4 genome"), which were all cloned as bacterial artificial chromosomes in Escherichia coli. Most of these intermediate clones were sequenced, and clones of all four 1/4 genomes with the correct sequence were identified. The complete synthetic genome was assembled by transformation-associated recombination cloning in the yeast Saccharomyces cerevisiae, then isolated and sequenced. A clone with the correct sequence was identified. The methods described here will be generally useful for constructing large DNA molecules from chemically synthesized pieces and also from combinations of natural and synthetic DNA segments. 10.1126/science.1151721. (shrink)

The aim of this paper is to present the method of Socratic proofs for seven modal propositional logics: K5, S4.2, S4.3, S4M, S4F, S4R and G. This work is an extension of [10] where the method was presented for the most common modal propositional logics: K, D, T, KB, K4, S4 and S5.

We argue, contrary to epistemological orthodoxy, that knowledge is not purely epistemic -- that knowledge is not simply a matter of truth-related factors (evidence, reliability, etc.). We do this by arguing for a pragmatic condition on knowledge, KA: if a subject knows that p, then she is rational to act as if p. KA, together with fallibilism, entails that knowledge is not purely epistemic. We support KA by appealing tothe role of knowledge-citations in defending and criticizing actions, and by giving (...) a principled argument for KA, based on the inference rule KB: if a subject knows that A is the best thing she can do, she is rational to do A. In the second half of the paper, we consider and reject the two most promising objections to our ease for KA, one based on the Gricean notion of conversational implicature and the other based on a contextualist maneuver. (shrink)

In this work we develop goal-directed deduction methods for the implicational fragment of several modal logics. We give sound and complete procedures for strict implication of K, T, K4, S4, K5, K45, KB, KTB, S5, G and for some intuitionistic variants. In order to achieve a uniform and concise presentation, we first develop our methods in the framework of Labelled Deductive Systems [Gabbay 96]. The proof systems we present are strongly analytical and satisfy a basic property of cut admissibility. We (...) then show that for most of the systems under consideration the labelling mechanism can be avoided by choosing an appropriate way of structuring theories. One peculiar feature of our proof systems is the use of restart rules which allow to re-ask the original goal of a deduction. In case of K, K4, S4 and G, we can eliminate such a rule, without loosing completeness. In all the other cases, by dropping such a rule, we get an intuitionistic variant of each system. The present results are part of a larger project of a goal directed proof theory for non-classical logics; the purpose of this project is to show that most implicational logics stem from slight variations of a unique deduction method, and from different ways of structuring theories. Moreover, the proof systems we present follow the logic programming style of deduction and seem promising for proof search [Gabbay and Reyle 84, Miller et al. 91]. (shrink)

In this paper, the problem of purifying an assumption-based theory KB, i.e., identifying the right extension of KB using knowledge-gathering actions (tests), is addressed. Assumptions are just normal defaults without prerequisite. Each assumption represents all the information conveyed by an agent, and every agent is associated with a (possibly empty) set of tests. Through the execution of tests, the epistemic status of assumptions can change from "plausible" to "certainly true", "certainly false" or "irrelevant", and the KB must be revised so (...) as to incorporate such a change. Because removing all the extensions of an assumption-based theory except one enables both identifying a larger set of plausible pieces of information and renders inference computationally easier, we are specifically interested in finding out sets of tests allowing to purify a KB (whatever their outcomes). We address this problem especially from the point of view of computational complexity. (shrink)