An Adequate theory of meaning and truth is semantically important. Such a theory necessarily includes in its analysis nonentities, items that do not exist. So what is semantically, and hence logically, important is bound to include nonentities. In virtue of the modifier ‘semantically“, the first premiss is analytic, and it is comparatively uncontroversial. By contrast the second premise of the syllogism, which we want to stick to, is decidedly controversial. So too is the thesis – which implies the inadequacy of (...) classical logical theories – that there are a great many natural language statements, statements an adequate theory should be able to treat of, which cannot be analysed logically, and semantically, without the equivalent of an appeal to nonentities. Defence of the thesis has been somewhat piecemeal, taking the form that all the theories so far offered which try to dispense with nonentities break down or run into insuperable difficulties, difficulties which are readily surmounted given appropriate talk about nonentities. In what follows we shall outline more general sorts of argument for the thesis, designed to show that no theory which dispenses with nonentities as objects of discourse can do justice to the data. (shrink)

The paper considers the morality of nuclear energy development as it concerns future people, especially the creation of highly toxic nuclear wastes requiring long?term storage. On the basis of an example with many parallel moral features it is argued that the imposition of such costs and risks on the future is morally unacceptable. The paper goes on to examine in detail possible ways of escaping this conclusion, especially the escape route of denying that moral obligations of the appropriate type apply (...) to future people. The bulk of the paper comprises discussion of this philosophical issue, including many arguments against assigning obligations to the future drawn both from analyses of obligation and from features of the future such as uncertainty and indeterminacy. A further escape through appeal to moral conflict is also considered, and in particular two conflict arguments, the Poverty and Lights?going?out arguments are briefly discussed. Both these escape routes are rejected and it is concluded that if the same standards of behaviour are applied to the future as to the present, nuclear energy development is morally unacceptable. (shrink)

Relevantism, as a matter of definition, rejects classical logic as incorrect and adopts instead a relevant logic as encapsulating correct inference. It rejects classical logic on the grounds that the rule of Material Detachment, from A and not A or B to infer B,, sometimes leads from truth to falsity. Relevantism — although promoted by some relevant logicians, and an integral part of ultralogic — has recently encountered heavy, but interesting, criticism from relevance logicians themselves.

The dissertation explores certain puzzles about fiction and existence. Some historical discussion of Brentano, Meinong and Russell sets the stage for an extended account of three neo-Meinongian semantic theories: those of Terence Parsons, Richard Routley , and Edward Zalta. It is argued that these authors rely on a false understanding of fiction. A distinction between setting out linguistic precedents in storytelling and following such precedents helps allow for the notion of being true in a story. However, fictional truth is (...) not a special case of truth nor is there any set of objects called 'fictional objects'. (shrink)

The logic BN4 can be considered as the 4-valued logic of the relevant conditional and the logic E4, as the 4-valued logic of entailment. The aim of this paper is to endow E4 with a 2-set-up Routley-Meyer semantics. It is proved that E4 is strongly sound and complete w.r.t. this semantics.

Problems of logical theory choice are current being widely dis- cussed in the context of anti-exceptionalist views on logic. According to those views, logic is not a special science among others, so, in particular, the methodology for theory choice should be the same in logic as for other scientific disciplines. Richard Routley advanced one such methodology which meshes well with anti-exceptionalism, and argued that it leads one to choosing one single logic, which is a kind of ultralogic. We argue (...) that the choice for only one correct system of logic may be rejected on the basis of the methodology proposed by Routley and, furthermore, that taking anti-exceptionalism about logic seriously recommends that a pluralist view of logic should be accepted. We call this view “full-blooded anti-exceptionalism”, and the resulting view on logic, lacking a proper name, “local pluralism”. (shrink)

The logic BN4 was defined by R.T. Brady in 1982. It can be considered as the 4-valued logic of the relevant conditional. E4 is a variant of BN4 that can be considered as the 4-valued logic of entailment. The aim of this paper is to define reduced general Routley-Meyer semantics for BN4 and E4. It is proved that BN4 and E4 are strongly sound and complete w.r.t. their respective semantics.

Ultralogic as Universal was drafted in 1976, appeared in 1977 as ‘Ultralogic as Universal?’ in The Relevance Logic Newsletter, 2 (1–2) and was reprinted as an appendix to Exploring Meinong’s Jungle...