From Sight to Light: The Passage from Ancient to Modern Optics

470 Pages·2014·2.025 MB·English

by  A. Mark Smith

From Sight to Light

From Sight to Light
the passage from ancient
to modern optics
A. Mark Smith
The University of Chicago Press Chicago & London
a. mark smith is a Curators’ Professor of History at the University of
Missouri–C olumbia. Among his numerous publications is an eight- volume critical Latin
edition and English translation of Alhacen’s De aspectibus.
The University of Chicago Press, Chicago 60637
The University of Chicago Press, Ltd., London
© 2015 by The University of Chicago
All rights reserved. Published 2015.
Printed in the United States of America
24 23 22 21 20 19 18 17 16 15 1 2 3 4 5
isbn- 13: 978- 0- 226- 17476- 1 (cloth)
isbn- 13: 978- 0- 226- 17493- 8 (e- book)
doi: 10.7208/chicago/9780226174938.001.0001
Library of Congress Cataloging-in-Publication Data
Smith, A. Mark, author.
From sight to light : the passage from ancient to modern optics / A. Mark Smith.
pages cm
Includes bibliographical references and index.
isbn 978-0-226-17476-1 (cloth : alkaline paper) — isbn 978-0-226-17493-8 (e-book)
1. Optics—History. I. Title.
qc352.s57 2014
535'.209—dc23
2014015929
o This paper meets the requirements of ansi/niso z39.48- 1992 (Permanence of Paper).
C o n t e n t s
Preface ix
chapter 1 Introduction / 1
chapter 2 The Emergence of Optics as a Science: The Greek and Early
Greco- Roman Background / 23
1 Early Intimations 25
2 Physical and Psychological Theories of Vision 29
3 The Anatomical and Physiological Grounds of Vision 36
4 Theories of Color and Color Perception 43
5 The Euclidean Visual Ray Theory 47
6 Euclidean Catoptrics 55
7 Burning Mirrors and the Analysis of Focal Properties 68
8 Conclusion 72
chapter 3 Ptolemy and the Flowering of Greek Optics / 76
1 The Ptolemaic Account of Visual Perception 80
2 The Ptolemaic Account of Reflection 92
3 The Ptolemaic Account of Refraction 108
4 Atmospheric Refraction and the Moon Illusion 121
5 Conclusion 127
chapter 4 Greco- Roman and Early Arabic Developments / 130
1 Plotinus’s Theory of Visual Perception 134
2 The Later De anima Commentators 143
3 Saint Augustine’s Psychological Model: The Inward Ascent 150
4 The Arabic Transition: The De anima Tradition 155
5 The Arabic Transition: Geometrical Optics 166
6 Conclusion 178
chapter 5 Alhacen and the Grand Synthesis / 181
1 The Elements of Alhacen’s Analysis 184
2 Visual Discrimination, Perception, and Conception 189
3 Reflection and Its Visual Manifestations 195
4 Refraction and Its Visual Manifestations 206
5 Conclusion 224
chapter 6 Developments in the Medieval Latin West / 228
1 Background to the Translation Movement 232
2 The Translation Movement and the Inroads of Aristotelianism 242
3 The Scholastic Analysis of Perception and Cognition 245
4 Geometrical Optics and the Evolving Science of Perspectiva 256
5 Conclusion 275
chapter 7 The Assimilation of Perspectivist Optics during the Later Middle
Ages and Renaissance / 278
1 Optics as a Quadrivial Pursuit in the Arts Curriculum 280
2 Theology and the Emergence of Optical Literacy 287
3 Optical Motifs in Literature 291
4 Renaissance Art, Naturalism, and Optics 298
5 Conclusion 316
chapter 8 The Keplerian Turn and Its Technical Background / 322
1 Technological, Social, and Cultural Changes: 1450– 1600 323
2 Rethinking Concave Mirrors and Convex Lenses 333
3 Rethinking the Eye 350
4 Kepler’s Analysis of Retinal Imaging 353
5 The Analytic Turn 363
6 The Epistemological Turn 367
7 Conclusion 370
chapter 9 The Seventeenth- Century Response / 373
1 The Conceptual and Cultural Context for the Keplerian Turn 376
2 Extending Vision in Both Directions 381
3 New Theories of Light 391
4 Recasting Color 400
5 The Epistemological Consequences 408
6 Conclusion 415
Bibliography 417
Index 441

P r e f a c e
The merest glance at any modern optics textbook leaves no doubt that, as cur-
rently understood, the science of optics is about light, about its fundamental
properties and how they determine such physical behavior as reflection, re-
fraction, and diffraction. But this understanding of optics and its appropriate
purview is relatively new. For the vast majority of its history, the science of
optics was aimed primarily at explaining not light and its physical manifesta-
tions, but sight in all its aspects from physical and physiological causes to per-
ceptual and cognitive effects. Consequently, light theory was not only regarded
as subsidiary to sight theory but was actually accommodated to it. And so it re-
mained until the seventeenth century, when the analytic focus of optics shifted
rather suddenly, and definitively, from sight to light. Marking the turn from
ancient toward modern optics, this shift of focus evoked an equivalent shift in
the order of analytic priority. Henceforth, sight theory would become increas-
ingly subsidiary to light theory, the former now accommodated to the latter.
Why this particular turn at this particular time? That is the formative ques-
tion for this study, and in response I will argue that Johannes Kepler’s theory of
retinal imaging, which was published in 1604, was instrumental in prompting
the turn, as well as in giving it direction and shape, hence my later character-
ization of the turn as Keplerian. In support of this argument, I will show how
Kepler’s theory of retinal imaging not only fit within, but also transcended a
long- evolving optical tradition that traced back to Greek antiquity via the Mus-
lim Middle Ages. More to the point, I will show how the optical analysis that
emerged within this tradition was driven by the need to explain how the visual
process can yield a faithful mental picture of physical reality from the initial