The Story of Psychology

by Morton Hunt

  The Rediscovery of the Mind

  Wertheimer’s theory that the mind adds structure and meaning to incoming sensations was distinctly out of step with the antimentalist psychology that had been dominant in Germany for nearly half a century and in America for a generation.

  His theory was also out of step with the Zeitgeist of 1910, which centered on the transformation of life and thought by the physical sciences and technology. The electric light was radically altering nighttime in cities and even remote towns, the automobile was changing the habits of nations, airplanes were becoming capable of sustained flight (Louis Blériot had flown across the English Channel), Marie Curie had just isolated radium and polonium, Rutherford was working out his theory of atomic structure, Zeppelin passenger service had recently begun, and Lee De Forest had lately patented the radio tube. The New Psychology was in harmony with such developments; mentalist psychology seemed more than ever metaphysical, unscientific, and passé.

  But for some years a number of psychologists had considered Wundtian psychology barren and confining because it did not deal with complex forms of experience such as emotions, thinking, learning, and creativity—the most important aspects of human life. James, Galton, Binet, Freud, and the members of the Würzburg School, though they had dissimilar concerns, were all interested in and had been investigating phenomena that could be explained only in terms of higher mental processes.

  In addition, other researchers had been turning up bits of evidence that perceptions are not identical with the sensations received by the retina or other sense organs but are the mind’s interpretation of the data in those sensations.

  As far back as 1890, Christian von Ehrenfels, an Austrian psychologist, pointed out that when a melody is transposed, every note is changed, yet we hear the very same melody. He explained that we recognize the sameness of relations among the parts of the whole—what he called the melody’s Gestaltqualität or “form quality,” a crucial characteristic perceived by the mind, rather than the ears.

  Ernst Mach, a physicist with an interest in psychology, noted in 1897 that when we see a circle at different angles, it seems circular to us even though it looks ellipsoidal to a camera, and that when we see a table from different angles, the image on the retina changes but the inner experience of seeing a table does not. The mind interprets the sensations to mean what it knows the object to be.

  In 1906 Vittorio Benussi, experimenting with the famous Müller-Lyer illusion, in which two lines (the horizontal ones in the following illustration) look different in length although they are exactly the same, found that even when he told his subjects to concentrate on the horizontal lines, they could not make themselves ignore the whole figure; they could reduce the illusion but not eliminate it.

  FIGURE 2

  The Müller-Lyer illusion

  And while Wertheimer was conducting his first experiment in Frankfurt, David Katz, a psychologist at Göttingen, was exploring the phenomena of “brightness constancy” and “color constancy.” When we see an object in shadow, he found, we perceive it as having the same brightness and color as when we see it in sunlight, even though objectively it is darker and its color different. We see it, that is, within a known context.

  Wertheimer, Koffka, and Köhler had all been exposed to such findings and concepts in their training, and had all been influenced at Berlin by Carl Stumpf, who had imported phenomenology from philosophy into psychology. (In phenomenological psychology, the primary materials of research are everyday real-life experiences, not elemental sensations and feelings.) Wertheimer and Koffka had also studied at Würzburg, where the research emphasis was on thought processes. All three, moreover, had done research involving higher mental functions: Wertheimer on the thinking of feeble-minded children and patients with reading disorders, Koffka in his dissertation on rhythmic Gestalten,* Köhler in his on the psychology of acoustics.

  Still, they were a distinctly dissimilar threesome, and hardly looked like an intellectual attack force capable of assaulting and defeating Wundtian psychology.

  Wertheimer, reared in Prague, was a Jew. Boyish of feature but balding, he sported a huge, martial, Bismarckian mustache but was poetic, musically gifted, warm, humorous, and cheerful. He was an exciting and fluent speaker; his ideas brimmed and bubbled over. But reining in his thoughts to set them down on paper was so difficult and painful for him that he was genuinely phobic about writing.

  Koffka, a Berliner, was half Jewish. Small and frail, with a long, thin face and a somber look, he was introverted, sensitive, and insecure; inexplicably, these traits, though they made him an uninspiring lecturer, endeared him to his female students. Ill at ease at the rostrum, he was comfortable at the writing table and produced systematic, scholarly expositions of the Gestalt psychology.

  Köhler, a Gentile born in Estonia and reared in Wolfenbüttel, Germany, was hawk-featured, with a short, stiff thatch of hair parted in the middle. He was the most painstaking experimenter of the three, and later became a strong institute administrator. Arrogant, stiff, and formal in person—he had to know someone socially for ten years before he would use the personal du instead of the formal Sie— in his writing he could be surprisingly relaxed and charming.

  In the end, the differences among the three produced an advantageous specialization of function. As one history of the Gestalt movement puts it, Wertheimer was “the intellectual father, thinker, and innovator,” Koffka “the salesman of the group,” and Köhler “the inside man, the doer.”5

  But only one of the three ever held a major position in the psychological establishment. Wertheimer, his way impeded by anti-Semitism and his limited output of publications, was for years merely a lecturer, and later a Professor Extraordinarius at the University of Berlin. Not until 1929, when he was forty-nine, did he finally become a full professor (at Frankfurt), only to have to flee abruptly four years later when the Nazis came to power. He emigrated to the United States, where he taught at the New School for Social Research but never held a major chair in psychology.

  In Germany, Koffka rose only to the rank of Professor Extraordinarius at the University of Giessen. He gave a series of lectures in America and in 1927 obtained a full professorship at Smith College—not a center of psychological research—and remained there for the rest of his life.

  Köhler alone achieved major status in Germany. After several years of teaching and over six years of brilliant experimental work in the Canary Islands, in 1921 he was appointed head of the Psychological Institute at the University of Berlin—the premier post in German psychology—at the age of thirty-four, and made it a center of Gestalt studies. But he held the post only fourteen years; in 1935, after courageously but vainly struggling to keep Nazi influence out of the institute, he resigned, came to America, and spent the rest of his career at Swarthmore College.

  Yet even before Köhler rose to his high position at Berlin, the three young men, in only ten years, breached the defenses of Wundtian psychology and established the legitimacy of their new mentalism—a psychology of the mind based on demonstrations and experimental evidence rather than on rationalist arguments and metaphysical speculations.

  Although they published relatively little in that time (partly because of the disruptions of World War I), it was enough to show that Gestalt theory offered a better explanation than earlier cognitive psychologies of both perception and higher mental functions. Their evidence was so striking and their arguments so plausible that by 1921 Gestalt psychology had begun to supplant Wundtian psychology, as evidenced by Köhler’s appointment.6

  Until the mid-1930s, Gestaltism was a major force in German psychology and a growing one in many other countries. It had only limited effect on American psychology before the arrival of the triumvirate between 1927 and 1935. Then, although none of the men held a leading position in the American psychological establishment, their ideas infiltrated psychological thinking and slowly began to expand it beyond the confines of behaviorism.

  The Laws
of Gestalten

  From the outset, Wertheimer saw Gestalt theory as far more than an explanation of perception; he believed it would prove to be the key to learning, motivation, and thinking.

  He based this view not only on the odds and ends of evidence offered by the predecessors of Gestalt theory but on some early research of his own. Shortly after his Frankfurt work on the illusion of motion, he was asked by the director of the children’s clinic at the Psychiatric Institute of Vienna to find ways of teaching deaf-mute children. One method he experimented with consisted of his building a simple bridge with three wooden blocks while a deaf-mute child watched, and then dismantling it. The child would then try it, and usually, after one or two mistakes, would catch on and successfully build a number of bridges of different shapes and sizes. The child’s thinking, it appeared to Wertheimer, was based not on the number and size of the items used in the demonstration but on the perception of a stable configuration—a Gestalt—in which both uprights are of the same length and are positioned toward the ends of the horizontal piece.7

  Wertheimer also read anthropological reports of numerical thinking by primitive peoples and wrote a paper on it in 1912. Speakers of certain South Sea languages, he learned, have different ways of counting fruit, money, animals, and men; each way represented a Gestalt appropriate to the item. He also discovered that people who lack our abstract system of grouping and numbering use natural groupings as numerical thinking. A primitive man about to build a hut might not count the number of vertical posts needed but would know without counting what the hut’s framework should look like and, thus, how many posts to seek.8

  Using these data plus his experiments at Frankfurt, Wertheimer drew up the outlines of a new psychology in a 1913 series of lectures. The central doctrine was that our mental operations consist chiefly of Gestalten rather than strings of associated sensations and impressions, as followers of Wundt and associationists believed. A Gestalt, he said, was not a mere accumulation of associated bits but a structure with an identity; it was different from and more than the sum of its parts. The acquisition of knowledge often took place through a process of “centering” or structuring and thereby seeing things as an orderly whole.9

  Although Wertheimer envisioned Gestalt theory as the basis of an entire psychology, much of his research and more than half the research of all Gestalt psychologists in the early years dealt with perception.*10 Within a dozen years the three leading Gestaltists, their students, and several other Gestalt-oriented psychologists had discovered a number of principles of perception, or “laws of Gestalten.” Wertheimer, drawing on his and others’ findings, named and discussed a handful of the major laws in one of his rare papers in 1923,11 and as time went on he, his colleagues, and their students discovered many others. (Eventually 114 laws of Gestalten were named.12) Here are a few of the more important ones:

  Proximity: When we see a number of similar objects, we tend to perceive them as groups or sets of those which are close to each other. Wertheimer’s simple demonstration:

  FIGURE 3

  The Law of Proximity: a simple case

  People shown the line of dots, he found, spontaneously see it as pairs of dots close to each other (ab/cd/ …), and while it could also be construed as pairs of widely spaced dots with little room between the pairs (a/bc/de/ …), no one sees it that way, and most people cannot even make themselves do so. A more striking example:

  FIGURE 4

  The Law of Proximity: a more extreme case

  Here one sees lines made up of three closely spaced dots, tilted slightly to the right of the vertical; one does not see, and can see only with difficulty, an alternative structure—lines made up of three widely spaced dots, tilted far to the left of the vertical.

  Similarity: When similar and dissimilar objects are mingled, we see the similar ones as groups:

  FIGURE 5

  The Law of Similarity: a simple example

  The similarity factor can, in fact, overcome the proximity factor. In the left-hand box below, we tend to see four groups of closely spaced objects; in the right-hand box, two sets of dispersed but similar objects.

  FIGURE 6

  The Law of Similarity: a more complex example

  Continuation or direction: In many patterns, we tend to see lines that have a coherent continuation or direction; this is why we are able to pick out a meaningful shape from a bewildering background, as we do in “hidden figure” puzzles. Such a line or shape is a “good Gestalt”—one with inner coherence or inner necessity. In this pattern, for instance, we can force ourselves to see two curved pointed figures, AB and CD, but what we tend to see is the more natural Gestalt of two intersecting curves, AC and BD. The factor of continuation can be astonishingly powerful. Consider these figures—

  FIGURE 7

  The Law of Continuation: two curves or two pointed shapes?

  FIGURE 8

  Two figures, easily seen as distinct

  and now this one, a merger of the previous two:

  FIGURE 9

  The same figures, now visually inseparable

  It is virtually impossible to see the originals in the merged figure because of the dominance of the continuous wavy line.

  Prägnanz: The related English word “pregnancy” does not convey Wertheimer’s meaning, which is “the tendency to see the simplest shape.” Much as physical laws cause a soap bubble to assume the simplest possible shape, so the mind tends to see the simplest Gestalten in complex patterns. This figure

  FIGURE 10

  The Law of Prägnanz: We see the simplest possible shapes.

  could be interpreted as an ellipse with a right-angled segment cut out of the right side of it touching a rectangle with a curved chunk cut out of the left side of it. But that is not what we see; we see the far simpler image of a whole ellipse and a whole rectangle overlapping.

  Closure: This is a special and important case of the Law of Prägnanz. When we see a familiar or coherent pattern with some missing parts, we fill them in and perceive the simplest and best Gestalt. We see this as a star instead of the five V’s that make it up.

  FIGURE 11

  The Law of Closure: We supply what is missing.

  In the 1920s, the Gestalt psychologist Kurt Lewin noticed that a waiter could easily remember the details of a customer’s bill if it had not yet been paid, but as soon as it was paid he forgot the details. It occurred to him that this was an instance of closure in the area of memory and motivation. As long as the transaction was incomplete, it lacked closure and generated tension, maintaining memory, but as soon as closure was achieved, the tension and the memory disappeared.13

  A student of Lewin’s, a Russian psychologist named Bluma Zeigarnik, put his conjecture to the test in a well-known experiment. She assigned a number of volunteers a series of simple tasks—making clay figures, solving arithmetic problems—allowing them to complete some of the tasks but interrupting them during others on a pretext and not letting them finish the work. A few hours later, when she asked them to recall the tasks, they remembered the uncompleted ones about twice as well as the completed ones, confirming Lewin’s guess.14 The study made her famous, in a small way; to this day, psychologists writing about motivation refer to the “Zeigarnik effect.”

  Figure-ground perception: When we pay attention to an object, we see little or nothing of the background; we see the face we are looking at, not the room or landscape beyond it. In 1915 Edgar Rubin, a psychologist at the University of Göttingen, explored this “figure-ground” phenomenon—the mind’s ability to focus attention on a meaningful pattern and ignore the rest of the data. He used a number of test patterns, one of which, the so-called Rubin vase, is familiar to almost everyone:

  FIGURE 12

  The Rubin vase: Pottery or profiles?

  If you look at the vase, you do not see the background; if you look at the background—two faces in profile—you do not see the vase. Moreover, you can will yourself to see whichever you choose; will a
pparently does exist, in spite of the New Psychologists and the behaviorists.

  Size constancy: An object of known size, when far off, projects a tiny image on the retina, yet we sense its real size. How do we manage that? Associationists said that we learn from experience that remote objects look small and pale, and we associate these clues with distance. Gestaltists found this explanation simplistic and contrary to new evidence. Very young chicks were trained to peck only at larger grains of feed. When the habit was firmly established, the larger grains were put at a distance, where they looked smaller than the nearby small grains, but the chicks unhesitatingly went for the larger ones. An eleven-month-old baby girl was trained (by means of a reward) to choose the larger of two side-by-side boxes. The larger box was then moved far enough away for its retinal image to be only 1/15 the area of the smaller box, but she still chose it.15

  We sense that distant objects are as large as when they are near because of the mind’s organization of data in terms of relationships—to adjoining known objects, for instance, or to perspective-giving features.16 The two illustrations in Figure 13, from a relatively recent textbook of perception, make the point:

  FIGURE 13

  Perspective gives clues to size.

  In the left-hand panel, the relationship of the farther man to things near him and to the hallway enables us to perceive him as being as large as the nearer man. Yet on one’s retina the image of the farther man is very much smaller, as the right-hand panel shows.