Claudio Calosi

Quantum mechanics and Priority Monism

The paper address the question of whether quantum mechanics (QM) favors Priority Monism, the view according to which the Universe is the only fundamental object. It develops formal frameworks to frame rigorously the question of fundamental mereology and its answers, namely (Priority) Pluralism and Monism. It then reconstructs the quantum mechanical argument in favor of the latter and provides a detailed and thorough criticism of it that sheds furthermore new light on the relation between parthood, composition and fundamentality in QM.

Parthood and Composition in Quantum Mechanics

The paper deals with parts and wholes in quantum theory. It addresses a much neglected question, namely of what mereological theory are quantum systems a model of. It argues that they are at least a model of the so called Closed Extensional Mereology. It then goes on to address the question of whether quantum theory favors a particular answer to what is known as the special composition question, i.e. what are the sufficient and necessary conditions a set of entities has to meet in order to have a mereological sum. It is suggested that quantum mechanics by itself falls short to yield a definitive answer to that question and different possible suggestions are explored. One of them is that quantum theory, together with some mild assumptions, such as the one that maintains that there are no uninstantiatedproperties, delivers at least a sufficient condition for having a mereological sum. This condition turns out to be that the quantum system is in an entangled state.

Extensionality, Multilocation, Persistence

The paper addresses various questions about the logical and metaphysical relations between notions of parthood, location and persistence. In particular it argues that the conjunction of mereological extensionalism and multilocation, is highly problematic, if not utterly inconsistent. It thus provides an alternate route to reject multilocation, one that does not rely on Barker and Dowes well known argument, at least for those who endorse extensionality of parthood. It then argues that other major metaphysical theses such as three-dimensionalism turn out to be at odds with extensionalism.

A Threat for Physicalism : a New Gedankenexperiment

We present a new thought experiment that raises a threat for Minimal Physicalism, i.e. the thesis according to which mental properties supervene on physical properties. Our proposal is an example of the so called hard problems in philosophy of mind, in particular the problem of maximal consciousness. We do not however presuppose anything about its very nature apart from the minimal, weak assumption that it is determined by first order mental properties. We argue that (i) either Minimal Physicalism is unable to give an adequate account of the new thought experiment we present or (ii) has to explain the fact that two numerically distinct but physically indistinguishable individuals have different maximal consciousness due to their spatial location. We contend that this last conclusion is strongly at variance with our contemporary scientific image of the world. Presentiamo qui un nuovo esperimento mentale, che costituisce un problema per il fisicalismo, inteso come la tesi secondo cui le proprieta mentali sopravvengono su quelle fisiche. Mostriamo che se il fisicalismo fosse vero, dovremmo spiegare il fatto che due individui numericamente distinti ma fisicamente indistinguibili hanno coscienza diversa a causa della loro differente collocazione spaziale. Questa conclusione e fortemente in contrasto con la nostra attuale immagine scientifica del mondo.

Composition, identity, and emergence

Composition as Identity (CAI) is the thesis that a whole is, strictly and literally, identical to its parts, considered collectively. McDaniel [2008] argues against CAI in that it prohibits emergent properties. Recently Sider [2014] exploited the resources of plural logic and extensional mereology to undermine McDaniel’s argument. He shows that CAI identifies extensionally equivalent pluralities – he calls it the Collapse Principle (CP) – and then shows how this identification rescues CAI from the emergentist argument. In this paper I first give a new generalized version of both the arguments. It is more general in that it does not presuppose an atomistic mereology. I then go on to argue that the consequences of CP are rather radical. It entails mereological nihilism, the view that there are only mereological atoms. I finally show that, given a mild assumption about property instantiation, namely that there are no un-instantiated properties, this argument entails that CAI and emergent properties are incompatible after all.

An elegant universe

David Lewis famously endorsed Unrestricted Composition. His defense of such a controversial principle builds on the alleged innocence of mereology. This innocence defense has come under different attacks in the last decades. In this paper I pursue another line of defense, that stems from some early remarks by van Inwagen. I argue that Unrestricted Composition leads to a better metaphysics. In particular I provide new arguments for the following claims: Unrestricted Composition entails extensionality of composition, functionality of location and four-dimensionalism in the metaphysics of persistence. Its endorsement yields an impressively coherent and powerful metaphysical picture. This picture shows a universe that might not be innocent but it is certainly elegant.

De li accidiosi che son avversi al possibile

[Pubblicato in Rivista Italiana di Filosofia Analitica Junior, 5:2 (2014), 101‐127] Antefatto: Nella primavera del 2014 abbiamo avuto l’onore e il piacere di dare alle stampe un volume contenente la trascrizione fedele di un poema anonimo in ventotto canti intitolato Le tribolazioni del filosofare. Comedia metaphysica ne la quale si tratta de li errori & de le pene de l’Infero (RomaBari, Editori Laterza). Il poema ‐ composto interamente in terzine incatenate di versi endecasillabi, in volgare toscano ‐ tratta del viaggio allegorico del Poeta attraverso il buio «Infero» dell’intelletto, sotto la guida di Socrate, alla ricerca di una via d’uscita dalla condizione di stallo e confusione diffusa nella quale egli sarebbe malamente precipitato. Piu precisamente, l’Infero e strutturato in una serie di Cerchi concentrici che si succedono verso un abisso sempre piu buio e profondo, e ciascun Cerchio (dieci in tutto, alcuni dei quali suddivisi in piu Gironi, Zone o Bolge) rappresenta un grave «errore» filosofico a cui corrisponde una «pena» altrettanto severa per quei pensatori che se ne sarebbero macchiati nel corso della storia. Il viaggio del Poeta e appunto il viaggio liberatorio di chi ha la pazienza e l’umilta intellettuale ‐ ma anche il coraggio ‐ di attraversare ogni Cerchio apprendendo «l’errori e da li errora». Come abbiamo avuto modo di scrivere nell’introduzione al volume, il poema presenta evidenti analogie, sul piano dello stile come su quello dell’architettura complessiva, con la prima cantica della Commedia di Dante Alighieri, benche non sia possibile determinare con certezza il nesso tra le due opere. Al momento possiamo solo confermare che le analogie sono tante e tali da non lasciare dubbi sul fatto che i due autori non abbiano operato in isolamento: o il Poeta trasse ispirazione da Dante per il suo poema filosofico (peraltro affiancato da un secondo componimento, per ora inedito, dedicato alle «virtu» e ai «premi» di un luogo chiamato «Empireo»), ovvero fu Dante stesso a ispirarsi al Poeta per il suo poema divino. In effetti la secon

Is the mind a quantum computer

The paper provides a critical assessment of Quantum Artificial Intelligence, roughly the view that the human mind can be effectively simulated by a quantum computer. In particular it raises several independent problems for such a view, namely a supervenience problem, a quantum measurement problem, a decoherence problem and an indiscernibility problem. Il lavoro presenta una valutazione critica della Intelligenza Artificiale Quantistica, la tesi secondo cui la mente umana puo essere effettivamente simulata da un computer quantistico. In particolare solleva diversi indipendenti problemi per questa tesi, un problema di sopravvenienza, un problema di misurazione, un problema di decoerenza e un problema di indiscernibilita.

Holism as an empirically meaningful metaphysical hypothesis

Quantum mechanics is often credited for having clearly shown that the whole is something over and above the sum of its parts. We want to assess whether this is really the case, and if so, in what sense. We argue that there is indeed a sense in which this is true. Our argument is that even a weak realistic interpretation of quantum mechanics renders a particular metaphysical principle about property instantiation, that we label Property Compositional Determinateness, untenable. Yet there is another metaphysical principle about composition that is usually maintained to imply that composition of parts exhausts the whole they are part of, namely Mereological Extensionalism. In this case, contrary to widespread agreement, we argue that quantum mechanics does not provide any reason, either direct or indirect, to abandon such principle. Spesso si riconosce alla Meccanica Quantistica di aver mostrato chiaramente che il tutto e piu della somma delle parti. In questo lavoro vogliamo indagare se, e in quale senso, questo e effettivamente il caso. Si argomenta che esiste un senso in cui tale affermazione e vera. Il nostro argomento principale e che una anche minima interpretazione realistica della Meccanica Quantistica rende un principio che chiamiamo Property Compositional Determinateness falso. Ma esiste un altro principio metafisico riguardante la composizione che spesso viene interpretato come implicare che la composizione delle parti esaurisca il tutto che compongono, il cosiddetto Mereological Extensionalism. In questo caso, contrariamente al generale consenso, si argomenta che la Meccanica Quantistica non suggerisce alcuna ragione, diretta o indiretta, in favore dell’abbandono di tale principio.