Vague Objects and Vague Identity: New Essays on Ontic Vagueness By AkibaKen and AbasnezhadAliSpringer, 2014. x + 360 pp. £117.00.

© The Authors 2017. Published by Oxford University Press on behalf of The Analysis Trust. All rights reserved. For Permissions, please email: [email protected] key virtue of Vague Objects and Vague Identity is how it includes so many essays that consider the particular ways vagueness manifests in different kinds of entities, including meanings, part-whole relations, the very small as understood by quantum mechanics, people, sensations, sets, ordinals, cardinals and abstractions. In every case, the author has something interesting to say not just (...) about vagueness but about the metaphysical category in question.One theme that unifies the diverse discussions is Gareth Evans’s brief 1978 note, ‘Can There Be Vague Objects?’ Let ‘▽’ stands for ‘it is indeterminate whether’, ‘λ’ stands for what it does in the lambda calculus, and ‘⊥’ be the absurdity constant. Then, Evans’s initial argument is: ▽ assumptionλx[▽]b 1... (shrink)

It has frequently been suggested that quantum mechanics may provide a genuine case of ontic vagueness or metaphysical indeterminacy. However, discussions of quantum theory in the vagueness literature are often cursory and, as I shall argue, have in some respects been misguided. Hitherto much of the debate over ontic vagueness and quantum theory has centered on the “indeterminate identity” construal of ontic vagueness, and whether the quantum phenomenon of entanglement produces particles whose identity is indeterminate. I argue that this way (...) of framing the debate is mistaken. A more thorough examination of quantum theory and the phenomenon of entanglement reveals that quantum mechanics is best interpreted as supporting what I call the “vague property” construal of ontic vagueness, where vague properties are understood in terms of determinable properties without the corresponding determinates. (shrink)

Might it be that world itself, independently of what we know about it or how we represent it, is metaphysically indeterminate? This article tackles in turn a series of questions: In what sorts of cases might we posit metaphysical indeterminacy? What is it for a given case of indefiniteness to be 'metaphysical'? How does the phenomenon relate to 'ontic vagueness', the existence of 'vague objects', 'de re indeterminacy' and the like? How might the logic work? Are there reasons for postulating (...) this distinctive sort of indefiniteness? Conversely, are there reasons for denying that there is indefiniteness of this sort? (shrink)

We consider the problem of therelationship between the quantum and theclassical domains from the point of view that itis possible to speak of a direct physicaldescription of quantum systems havingphysical properties. We put emphasis, inevidencing it, on the specific quantum conceptof indistinguishability of identical in aconceptual way (and not in a logical way in thevein of ``da Costa's school''). In essence, thesubsequent argumentation deals with therelationship between the classical and thequantum, with the problem of the quantum theoryof measurement. Even in (...) the absence of adefinitive response to this problem, the bestattitude for the time being, as we cannot reducethe classical and the quantum one to the other,seems to be to accept their pacific coexistence,and this is possible with the toleranceprinciple of the ``pragmatic truth'' developedfrom a logical point of view by Newton daCosta.RESUMO. As áreas quântica eclássica enquanto provisórioscoexistentes parallelos. Abordamos oproblema da relação entre as áreasdo quântico e do clássico considerandoque é possível falar de umadescrição física direta de sistemas quânticos tendo propriedades.Insistimos, para isto, sobre o conceitoespecificamente quântico daindicernabilidade dos idênticos de um ponto devista conceptual (não de um ponto de vistalógico à maneira da ``escola da Costa'')como evidenciando isto. O essencial daargumentação a seguir tem como enfoquea relação clássico-quântico, como problema da teoria quântica damedição. Mesmo não tendo umaresposta definitiva para este, a melhor atitudepor enquanto, já que não se podemreduzir um ao outro o clássico e oquântico, nos parece ser esta de aceitar suacoexistência pacífica, o que épossível com o princípio detolerância da ``verdade pragmática''desenvolvida logicamente por Newton da Costa. (shrink)

We investigate the higher-order modal logic , which is a variant of the system presented in our previous work. A semantics for that system, founded on the theory of quasi sets, is outlined. We show how such a semantics, motivated by the very intuitive base of Schrödinger logics, provides an alternative way to formalize some intensional concepts and features which have been used in recent discussions on the logical foundations of quantum mechanics; for example, that some terms like 'electron' have (...) no precise reference and that 'identical' particles cannot be named unambiguously. In the last section, we sketch a classical semantics for quasi set theory. (shrink)

The concept of indiscernibility in a structure is analysed with the aim of emphasizing that in asserting that two objects are indiscernible, it is useful to consider these objects as members of (the domain of) a structure. A case for this usefulness is presented by examining the consequences of this view to the philosophical discussion on identity and indiscernibility in quantum theory.

E.J. Lowe claims that quantum physics provides examples of ontic indeterminacy, of vagueness in the world. Any such claim must confront the Evans-Salmon argument to the effect that the notion of ontic indeterminacy is simply incoherent (Evans 1978, Salmon 1981: 243-46). Lowe argues that a standard version of the Evans-Salmon argument fails quite generally (Lowe 1994). Harold Noonan (1995) has outlined a non-standard version of the argument, but Lowe argues that this non-standard version fails for specifically quantum mechanical reasons (Lowe (...) 1997). He claims that it is perfectly coherent to suppose that his quantum case is an example of ontic indeterminacy. In this paper, I raise some objections to Lowe's claim. (shrink)

In order to understand consciousness one would benefit from developing a more eclectic intellectual style. Consciousness is, as proposed by almost everyone except the stubborn reductionists, a truly mysterious concept. Its study and dissection merits a multidisciplinary approach. Waving this multidisciplinary flag has positively enlarged the discussion and neurologists, psychiatrists, mathematicians, and so on, have moved to the philosophy of mind arena, first with caution and now with a more powerful voice. Identifying what we mean by consciousness is a first (...) step even when we want to deny its existence. The link between consciousness and some other mental activity is a logical next step and there is abundant literature doing this, but not all of them differentiate among associated yet different phenomena. (shrink)

This thesis analyses the ontological nature of quantum particles. In it I argue that quantum particles, despite their indistinguishability, are objects in much the same way as classical particles. This similarity provides an important point of continuity between classical and quantum physics. I consider two notions of indistinguishability, that of indiscernibility and permutation symmetry. I argue that neither sort of indistinguishability undermines the identity of quantum particles. I further argue that, when we understand in distinguishability in terms of permutation symmetry, (...) classical particles are just as indistinguishable as quantum particles; for classical physics also possesses permutation symmetry. (shrink)