The sequent system LDJ is formulated using the same connectives as Gentzen's intuitionistic sequent system LJ, but is dual in the following sense: (i) whereas LJ is singular in the consequent, LDJ is singular in the antecedent; (ii) whereas LJ has the same sentential counter-theorems as classical LK but not the same theorems, LDJ has the same sentential theorems as LK but not the same counter-theorems. In particular, LDJ does not reject all contradictions and is accordingly paraconsistent. To obtain a (...) more precise mapping, both LJ and LDJ are extended by adding a "pseudo-difference" operator which is the dual of intuitionistic implication. Cut-elimination and decidability are proved for the extended systems and , and a simply consistent but -inconsistent Set Theory with Unrestricted Comprehension Schema based on LDJ is sketched. (shrink)

Two things have been missing from discussions of Emerson and skepticism. The first—and the most glaring omission, given his precise, unambiguous definition of skepticism as “unbelief in cause and effect” (“Worship”)—is Emerson’s causationism. The second is his view of skepticism as organically related to a wide array of other forms of anti-realism or “romance.” Only the first can explain the second and thereby give us a better sense of how Emerson’s specific response to skepticism as a philosophical problem fits into (...) his broader, resolutely realist vision of the conduct of life. (shrink)

This book gives the first complete, fully historicized account of Emerson's metaphysics of cause and effect and its foundational position in his philosophy as a whole. Joseph Urbas proposes an intellectual biography of Emerson the metaphysician but also the life-story of a concept synonymous, in the Transcendentalist period, with life itself—the story of the principle at the origin of all being and change.

Emerson 's philosophical rehabilitation, begun in the late 1970s, has neglected an important branch of his thought: his metaphysics. Revisionist interpretations have generally followed Stanley Cavell's anti-metaphysical lead, privileging process and pluralism to the exclusion of any ultimate grounding principle. Russell Goodman's work takes Emerson scholarship in a new direction less hostile to metaphysics. His reading of Emerson 's "Nominalist and Realist" attempts to balance the principles of change and permanence, albeit in "unstable" alternation. What Goodman calls instability I call (...) synthesis or "bi-polarity," made possible by a metaphysical doctrine whose core principle is universal causation. Emerson 's "causationism" openly embraces both Nominalism and Realism as true to opposite poles of the same causal and ontological continuum—that of reality itself. (shrink)

Most psychological studies investigating the balance between stability and flexibility in decision making use specific restrictions in their scenarios. These restrictions are likely to affect decision process, and it is unclear which of the findings can be transferred to more naturalistic decision contexts that call for a balance between stability and flexibility. Therefore, the present study used a scenario that is inspired by the problem structure found in a particular domain: Adapt/Exchange decisions in modular chemical plants. In this setting, we (...) investigated whether participants engage in a thorough comparison of options and whether they perseverate on their previous choices when decision sequences increasingly favour one or the other option. The results suggest that instead of comparing options, participants used a satisficing strategy, checking whether Adapt was good enough and only computing an Exchange solution when it was not. Sequence effects were found, but their direction was opposite to the choice perseveration predicted from the literature: In sequences initially favouring Adapt, participants started exploring the Exchange option early on, while in sequences initially demanding Exchange, they preferred Adapt as soon as it became possible. The results raise questions about the application of psychological theories to complex decisions between qualitatively different options. (shrink)

In this paper, we introduce Speedith which is an interactive diagrammatic theorem prover for the well-known language of spider diagrams. Speedith provides a way to input spider diagrams, transform them via the diagrammatic inference rules, and prove diagrammatic theorems. Speedith’s inference rules are sound and complete, extending previous research by including all the classical logic connectives. In addition to being a stand-alone proof system, Speedith is also designed as a program that plugs into existing general purpose theorem provers. This allows (...) for other systems to access diagrammatic reasoning via Speedith, as well as a formal verification of diagrammatic proof steps within standard sentential proof assistants. We describe the general structure of Speedith, the diagrammatic language, the automatic mechanism that draws the diagrams when inference rules are applied on them, and how formal diagrammatic proofs are constructed. (shrink)