Cover image for Seeing double : shared identities in physics, philosophy, and literature
Seeing double : shared identities in physics, philosophy, and literature
Pesic, Peter.
Personal Author:
Publication Information:
Cambridge, Mass. : MIT Press, [2002]

Physical Description:
184 pages : illustrations ; 21 cm
Format :


Call Number
Material Type
Home Location
Central Library BF697 .P47 2002 Adult Non-Fiction Central Closed Stacks

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The separateness and connection of individuals is perhaps the central question of human life: What, exactly, is my individuality? To what degree is it unique? To what degree can it be shared, and how? To the many philosophical and literary speculations about these topics over time, modern science has added the curious twist of quantum theory, which requires that the elementary particles of which everything consists have no individuality at all. All aspects of chemistry depend on this lack of individuality, as do many branches of physics. From where, then, does our individuality come?

Author Notes

Peter Pesic is Tutor and Musician-In-Residence at St. John's College, Santa Fe.

Reviews 3

Booklist Review

The '60s comedy troupe Firesign Theater famously asked, "How can you be in two places at once when you're really nowhere at all?" And everyone chuckled at the pun on the idiomatic meaning of being nowhere: being a square. It turns out, however, that that question restates a central inquiry of science and philosophy, which literature often ponders, too--to wit, Is identity resemblance or distinction? That is, does identity consist of being exactly like something else or being distinguishable from it? As Pesic imparts, the answer to the questions about identity is yes, and the answer to Firesign Theater's laugh line is, "Easy, if you're physical." Those are the answers because physical reality consists of unchanging things that are exactly alike and changing things that are individually distinct. The irreducible particles of quantum physics can "be" in two places simultaneously--but nowhere in particular--because they are indistinguishable. Meanwhile, bodies comprising those particles are distinct and can't be in more than one place at once. Pesic arrives at this puzzling understanding of existence by starting with the ancient Greeks' consideration of the identity problem in literature, myth, and philosophy, and proceeding through medieval thought to the Newtonian era, the nineteenth-century eruption in physics, and quantum physics. In passing, he cites literary treatments of double identity to illustrate what the scientific controversies imply, and he suavely creates a masterpiece by saying much in little space. --Ray Olson

Publisher's Weekly Review

In this suggestive but almost terse volume, Pesic, a musician-physicist at St. John's College, probes the mysteries of individuality and identity in light of quantum theory. For Pesic, quantum theory poses a paradox: electrons and other elementary particles exhibit no individuality, yet we who are composed of these particles believe we are individuals. Every electron is so devoid of distinguishing features that one cannot even mark a particular electron to trace its history; they are perfectly identical instances of their species, a property Pesic christens "identicality." To explore the implications of identicality, Pesic looks not only to science but also to literature and philosophy. He considers Penelope's recognition of Odysseus in Homer's Odyssey, the ship of Theseus, Democritus, Leibniz, Kant, Martin Guerre, Conrad and Kafka, and hopscotches through the history of physics from Newton and Maxwell to Planck and the articulation of quantum theory in the 1920s. Pesic argues that the admittedly strange quantum realm becomes more intelligible if one treats the loss of individuality as a fundamental postulate rather than a peripheral consequence of scaling down the physical world. He concludes by suggesting how identicality may point to novel ways of viewing ourselves, perhaps as modes of a single field, existing through participation. The prose style is clear and accessible, the treatment concise and admirably suited for the author's goal of beginning "a thoughtful conversation among many people," including nonspecialists. But the issues are so large and compelling that the book's brevity is at times frustrating, particularly in its most crucial sections on quantum theory and its implications. Still, the book does a respectable job of opening the conversation it seeks. (Mar.) (c) Copyright PWxyz, LLC. All rights reserved

Choice Review

This delightful treatise addresses questions having to do with identity, individuality, and distinguishability. Trained as a physicist, Pesic (tutor and musician-in-residence, St. John's College) takes his readers on a dazzling ride through history, literature, physics, chemistry, and philosophy. When the ship in which the Athenians sailed every year to the isle of Delos to pay homage to Apollo needed repair and the Greek citizens decided to replace worn parts with identical pieces, would the ship, though indistinguishable from its original, still be the same ship after every part had been replaced? If electrons cannot be distinguished from one another, how is it possible to count them? In what lies the identity of an object if not in its individuality, i.e., its distinguishability from all others? Pesic offers no final answers to these riddles, but the implications are staggering. Does the absence of individuality at the quantum level apply at the macro level? If so, how is the cloned animal distinguished from the original? In the last two pages Pesic touches on the issue of identity in humans and suggests that perhaps individuals gain their identity through participation in the existence of the other. Highly recommended for upper-division undergraduates and above in psychology and a variety of disciplines. J. P. McKinney emeritus, Michigan State University

Table of Contents

Prologuep. 1
1 Commodity and Sacramentp. 7
2 The Ship of Theseusp. 15
3 Atoms and Monadsp. 25
4 Secret Sharersp. 39
5 Distinguishability and Paradoxp. 51
6 The Fields of Lightp. 69
7 Entanglementp. 85
8 Identicalityp. 101
9 The Silence of the Sirensp. 121
10 Beyond Beingp. 133
Epiloguep. 147
Notesp. 151
Acknowledgmentsp. 173
Indexp. 175

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