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Psychological Theories of Perception, Imagination and Mental Representation, and Twentieth Century Philosophies of Science

by Nigel J.T. Thomas
University of Leeds, Leeds U.K. 1987.


Below you can find my doctoral thesis (dissertation) from 1987, made freely available here for the first time. Despite its age, I believe that most of its arguments and claims still hold water. Furthermore, although some of the material has since been covered or superseded by later publications of mine, there is much that has not, and can only be found here. Despite the title, there is not much overt philosophy of science in it. It is mostly about the cognitive science of mental imagery.

The material is provided as a set of PDF files, so you will need Adobe Acrobat Reader, or some other PDF reader, such as Foxit, or my current favorite PDF-Xchange Viewer, to read them. These can be downloaded for free if you do not have them: (Adobe Acrobat downloadFoxit PDF Reader downloadPDF-Xchange Viewer download). Unfortunately, because they are scans of printed pages, and doing an OCR scan was not practicable, the PDF files are not internally searchable. However, there are quite good Name and Subject indexes, keyed to page numbers. (The indexes cover the notes as well as the main text, but not the bibliography.)

You can either access the individual PDF files via the links in the Table of Contents below, or, if you prefer, you can download the whole thing as a ZIP file (24.8MB) by clicking here and saving the file to your local hard drive. The ZIP file includes all the individual PDF files, plus an HTML contents page, similar to this page, which will allow you to access the various parts of the thesis in a (relatively) convenient way. When you have downloaded and unzipped, click on the HTML file entitled Contents to open it in your browser.

Checking citations:
Partly because of the limitations of the computer equipment and software available to me at the time the thesis was written, and partly because of my inexperience, at the time, in planning such things, looking up a citation is rather complicated. Citations are indicated in the text by a number in curly braces, thus: {17}. This indicates a note in the endnote file that goes with the relevant section of the thesis (neither my word processing software nor my printer could readily handle superscripted numbers). In the notes, the citations are given more or less in Harvard style (e.g., "Neisser (1976)"), and the publication details can then be looked up in the alphabetized bibliography. Unfortunately this means you need to open three PDF files (section of text, endnotes to that section, and bibliography) to check a citation. When an endnote contains substantive material as well as (or instead of) citations, the number in the curly braces in the main text is followed by an asterisk, thus: {8*}.

The early sections of the thesis were created on a BBC Micro Model B with 32 Kilobytes of RAM (of which 10-16K were used as video RAM whilst word processing), and no hard drive (though I did have an external 5¼" floppy drive). When that computer was stolen, it was replaced with a BBC Micro Model B+128, which had a whopping 128 Kilobytes of RAM (but still no hard drive). The thesis was printed on an NLQ ("Near letter quality") Kaga-Taxan dot matrix printer, and I used a program called Fontaid to program the printer with alternative fonts for headings and bold text (italics did not work well with NLQ), and to hand design certain special characters, such as letters with umlauts and other diacritics. (I had to get special permission from the University to submit the thesis printed by an NLQ rather than with a daisywheel printer. Laser printers were hugely expensive in those days, and I do not think inkjets were available at all.) The word processing software was Acorn's View 3, supplied on a ROM chip that you had to install inside the computer. Spellchecking was done with a separate program, ViewSpell, run from a floppy disc. However, View 3 provided no footnoting or endnoting capability, so I wrote my own software, in BBC BASIC, to process the files so as to turn text placed within curly braces in the body of the document into numbered endnotes in a separate file.

Psychological Theories of Perception, Imagination and Mental Representation, and Twentieth Century Philosophies of Science.
by Nigel J.T. Thomas
Unpublished Doctoral Dissertation, University of Leeds, 1987
(ASLIB Index to Theses, 37–iii, 4561)

Table of Contents

Click on the blue links for the PDFs of each section
Title page, Abstract, Contents, and List of Illustrations

What's it All About and Why are we Here? (A Personal Preface)

(pp. 1–23)
Notes to introduction
(pp. 449–453)

Part 1: Why Should We be Interested in Mental Imagery?


Chapter I.A: Imagery and Knowledge: an Old Story

    §I.A.1 Aristotle's Problem: Phantasia and Common Sense (pp. 25–34) Notes to §I.A.1 (pp. 453–456)
    §I.A.2 Phantasia, Imagination and Imagery (pp. 35–38) Notes to §I.A.2 (pp. 456–458)

Chapter I.B: The Banishment of the Mental Image from Experimental Psychology

    §I.B.1 The "Imageless Thought" Controversy (pp. 39–52) Notes to §I.B.1 (pp. 458–461)
    §I.B.2 Attitudes to Imagery, and Individual Differences (pp. 52–59) Notes to §I.B.2 (pp. 461–464)
    §I.B.3 J.B. Watson's Iconophobia (pp. 59–70) Notes to §I.B.3 (pp. 464–467)
    §I.B.4 The Gestalt Imagination (pp. 71–93) Notes to §I.B.4 (pp. 467–474)

Chapter I.C: The Imagery Revival

    §I.C.1 The Return of the Ostracized (pp. 94–109) Notes to §I.C.1 (pp. 474–477)
    §I.C.2 Dual Coding Theory (pp. 109–131) Notes to §I.C.2 (pp. 477–482)
    §I.C.3 Mental Rotation (pp. 132–149) Notes to §I.C.3 (pp. 482–485)
    §I.C.4 Image Scanning (pp. 149–174) Notes to §I.C.4 (pp. 485–491)
    §I.C.5 Imaginary Sizes (pp. 175–189) Notes to §I.C.5 (pp. 491–493)

Part II: Theories of Imagining


Chapter II.A: Mental Images as Pictures: a Historical Perspective

    §II.A.1 The Fundamental Types of Imagery Theory (pp. 191–199) Notes to §II.A.1 (pp. 493–495)
    §II.A.2 The Ancients (pp. 199–205) Notes to §II.A.2 (pp. 495–496)
    §II.A.3 The Moderns (pp. 205–214) Notes to §II.A.3 (pp. 496–498)

Chapter II.B: The "Quasi-Pictorial" Theory Today

    §II.B.1 Kosslyn's Model (pp. 215–222) Notes to §II.B.1 (pp. 498–501)
    §II.B.2 Pictorial Imagery and Imagination (pp. 223–229) Notes to §II.B.2 (pp. 501–502)
    §II.B.3 Are Quasi-Pictprial Theories Incoherent? (pp. 229–234) Notes to §II.B.3 (pp. 503–504)
    §II.B.4 Cognitive Penetration 1: Introspection and Vagueness (pp. 235–240) Notes to §II.B.4 (pp. 504–507)
    §II.B.5 Cognitive Penetration 2: Experimental Evidence and Reparsing (pp. 241–248) Notes to §II.B.5 (pp. 507–508)
    §II.B.6 Imagery and Spatial Knowledge in the Blind (pp. 248–269) Notes to §II.B.6 (pp. 508–513)*
    §II.B.7 Imaginary Montages (pp. 269–274) Notes to §II.B.7 (pp. 513–514)*

Chapter II.C: Imagination as Description

    §II.C.1 Images, Percepts, Descriptions, and Computers (pp. 275–282) Notes to §II.C.1 (pp. 514–517)
    §II.C.2 Simulating Imagery in Terms of Descriptions (pp. 282–295) Notes to §II.C.2 (pp. 517–519)
    §IIC.3 Can Descriptions Account for Image Effects? (pp. 295–310) Notes to §II.C.3 (pp. 519–522)
    §II.C.4 Imagery and Perceptual Processes (pp. 310–330) Notes to §II.C.4 (pp. 522–526)
    §II.C.5 'Propositional' Representation and Aristotle's Problem (pp. 331–350) Notes to §II.C.5 (pp. 526–529)

Chapter II.D: Imagination as Perceptual Activity

    §II.D.1 Precursors: The Motor Theory of the Mind and Imagery as Pretence (pp. 351–361) Notes to §II.D.1 (pp. 529–533)
    §II.D.2 Images and Eye Movements (pp.361–380) Notes to §II.D.2 (pp. 533–537)
    §II.D.3 Object Hypotheses and Hypothetical Instantiation (pp. 381–389) Notes to §II.D.3 (pp. 537–538)
    §II.D.4 James Gibson's Account of Perception (pp. 389–409) Notes to §II.D.4 (pp. 539–543)
    §II.D.5 Imagining and Cycling (pp. 409– 425) Notes to §II.D.5 (pp. 543–546)
    §II.D.6 The Activity Theory and the Experimental Evidence (pp. 425–437) Notes to §II.D.6 (pp. 546–548)
On Turning Philosophy into Science

(pp. 438–448)
Notes to Conclusion
(pp. 548–549)
Bibliography Name Index Subject Index
*The notes to §II.B.6 and §II.B.7 were inadvertently scanned as a single file.

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