This article has multiple issues. Please help talk page. (Learn how and when to remove these template messages) or discuss these issues on the(Learn how and when to remove this template message)
Gestalt psychology or gestaltism (German: Gestalt [??'?talt] "shape, form") is a philosophy of mind of the Berlin School of experimental psychology. Gestalt psychology is an attempt to understand the laws behind the ability to acquire and maintain meaningful perceptions in an apparently chaotic world. The central principle of gestalt psychology is that the mind forms a global whole with self-organizing tendencies. The assumed physiological mechanisms on which Gestalt theory rests are poorly defined and support for their existence is lacking. The Gestalt theory of perception has been criticized as being descriptive of the end products of perception without providing much insight into the processes that lead to perception. In the introduction of the vol 126 (2016) special issue of the journal Vision Research on Gestalt perception, the authors concluded that "even though they study the same phenomena as earlier Gestaltists, there is little theoretical coherence. What happened to the Gestalt school that always aspired to provide a unified vision of psychology? Perhaps there is, in fact, little that holds the classic phenomena of Gestalt psychology together."
This principle maintains that when the human mind (perceptual system) forms a percept or "gestalt", the whole has a reality of its own, independent of the parts. The original famous phrase of Gestalt psychologist Kurt Koffka, "The whole is other than the sum of the parts" is often incorrectly translated as "The whole is greater than the sum of its parts", and thus used when explaining gestalt theory, and further incorrectly applied to systems theory. Koffka did not like the translation. He firmly corrected students who replaced "other" with "greater". "This is not a principle of addition" he said. The whole has an independent existence.
In the study of perception, Gestalt psychologists stipulate that perceptions are the products of complex interactions among various stimuli. Contrary to the behaviorist approach to focusing on stimulus and response, gestalt psychologists sought to understand the organization of cognitive processes (Carlson and Heth, 2010). The gestalt effect is the capability of our brain to generate whole forms, particularly with respect to the visual recognition of global figures instead of just collections of simpler and unrelated elements (points, lines, curves, etc.).
The concept of gestalt was first introduced in philosophy and psychology in 1890 by Christian von Ehrenfels (a member of the School of Brentano). The idea of gestalt has its roots in theories by David Hume, Johann Wolfgang von Goethe, Immanuel Kant, David Hartley, and Ernst Mach. Max Wertheimer's unique contribution was to insist that the "gestalt" is perceptually primary, defining the parts it was composed from, rather than being a secondary quality that emerges from those parts, as von Ehrenfels's earlier Gestalt-Qualität had been.
Both von Ehrenfels and Edmund Husserl seem to have been inspired by Mach's work Beiträge zur Analyse der Empfindungen (Contributions to the Analysis of Sensations, 1886), in formulating their very similar concepts of gestalt and figural moment, respectively. On the philosophical foundations of these ideas see Foundations of Gestalt Theory (Smith, ed., 1988).
Early 20th century theorists, such as Kurt Koffka, Max Wertheimer, and Wolfgang Köhler (students of Carl Stumpf) saw objects as perceived within an environment according to all of their elements taken together as a global construct. This 'gestalt' or 'whole form' approach sought to define principles of perception--seemingly innate mental laws that determined the way objects were perceived. It is based on the here and now, and in the way things are seen. Images can be divided into figure or ground. The question is what is perceived at first glance: the figure in front, or the background.
These laws took several forms, such as the grouping of similar, or proximate, objects together, within this global process. Although gestalt has been criticized for being merely descriptive, it has formed the basis of much further research into the perception of patterns and objects (Carlson et al. 2000), and of research into behavior, thinking, problem solving and psychopathology.
The founders of Gestalt therapy, Fritz and Laura Perls, had worked with Kurt Goldstein, a neurologist who had applied principles of Gestalt psychology to the functioning of the organism. Laura Perls had been a Gestalt psychologist before she became a psychoanalyst and before she began developing Gestalt therapy together with Fritz Perls. The extent to which Gestalt psychology influenced Gestalt therapy is disputed, however. In any case it is not identical with Gestalt psychology. On the one hand, Laura Perls preferred not to use the term "Gestalt" to name the emerging new therapy, because she thought that the gestalt psychologists would object to it; on the other hand Fritz and Laura Perls clearly adopted some of Goldstein's work. Thus, though recognizing the historical connection and the influence, most gestalt psychologists emphasize that gestalt therapy is not a form of gestalt psychology.
Mary Henle noted in her presidential address to Division 24 at the meeting of the American Psychological Association (1975): "What Perls has done has been to take a few terms from Gestalt psychology, stretch their meaning beyond recognition, mix them with notions--often unclear and often incompatible--from the depth psychologies, existentialism, and common sense, and he has called the whole mixture gestalt therapy. His work has no substantive relation to scientific Gestalt psychology. To use his own language, Fritz Perls has done 'his thing'; whatever it is, it is not Gestalt psychology" With the Gestalt theory however, she restricts herself explicitly to only three of Perls' books from 1969 and 1972, leaving out Perls' earlier work, and Gestalt therapy in general.
There are clinical applications of Gestalt psychology in the psychotherapeutic field, foremost in Europe, e.g. Gestalt theoretical psychotherapy.
The school of gestalt practiced a series of theoretical and methodological principles that attempted to redefine the approach to psychological research. This is in contrast to investigations developed at the beginning of the 20th century, based on traditional scientific methodology, which divided the object of study into a set of elements that could be analyzed separately with the objective of reducing the complexity of this object.
The theoretical principles are the following:
Based on the principles above the following methodological principles are defined:
In the 1940s and 1950s, laboratory research in neurology and what became known as cybernetics on the mechanism of frogs' eyes indicate that perception of 'gestalts' (in particular gestalts in motion) is perhaps more primitive and fundamental than 'seeing' as such:
This is demonstrated by the dog picture, which depicts a Dalmatian dog sniffing the ground in the shade of overhanging trees. The dog is not recognized by first identifying its parts (feet, ears, nose, tail, etc.), and then inferring the dog from those component parts. Instead, the dog appears as a whole, all at once. Gestalt theory does not have an explanation for how this perception of a dog appears.
Reification is the constructive or generative aspect of perception, by which the experienced percept contains more explicit spatial information than the sensory stimulus on which it is based.
For instance, a triangle is perceived in picture A, though no triangle is there. In pictures B and D the eye recognizes disparate shapes as "belonging" to a single shape, in C a complete three-dimensional shape is seen, where in actuality no such thing is drawn.
Reification can be explained by progress in the study of illusory contours, which are treated by the visual system as "real" contours.
Multistability (or multistable perception) is the tendency of ambiguous perceptual experiences to pop back and forth unstably between two or more alternative interpretations. This is seen, for example, in the Necker cube and Rubin's Figure/Vase illusion shown here. Other examples include the three-legged blivet and artist M. C. Escher's artwork and the appearance of flashing marquee lights moving first one direction and then suddenly the other. Again, gestalt does not explain how images appear multistable, only that they do.
Invariance is the property of perception whereby simple geometrical objects are recognized independent of rotation, translation, and scale; as well as several other variations such as elastic deformations, different lighting, and different component features. For example, the objects in A in the figure are all immediately recognized as the same basic shape, which are immediately distinguishable from the forms in B. They are even recognized despite perspective and elastic deformations as in C, and when depicted using different graphic elements as in D. Computational theories of vision, such as those by David Marr, have provided alternate explanations of how perceived objects are classified.
The fundamental principle of gestalt perception is the law of prägnanz[de] (in the German language, pithiness), which says that we tend to order our experience in a manner that is regular, orderly, symmetrical, and simple. Gestalt psychologists attempt to discover refinements of the law of prägnanz, and this involves writing down laws that, hypothetically, allow us to predict the interpretation of sensation, what are often called "gestalt laws".
A major aspect of Gestalt psychology is that it implies that the mind understands external stimuli as whole rather than the sum of their parts. The wholes are structured and organized using grouping laws. The various laws are called laws or principles, depending on the paper where they appear--but for simplicity's sake, this article uses the term laws. These laws deal with the sensory modality of vision. However, there are analogous laws for other sensory modalities including auditory, tactile, gustatory and olfactory (Bregman - GP). The visual Gestalt principles of grouping were introduced in Wertheimer (1923). Through the 1930s and '40s Wertheimer, Kohler and Koffka formulated many of the laws of grouping through the study of visual perception.
Some of the central criticisms of Gestaltism are based on the preference Gestaltists are deemed to have for theory over data, and a lack of quantitative research supporting Gestalt ideas. This is not necessarily a fair criticism as highlighted by a recent collection of quantitative research on Gestalt perception.
In some scholarly communities, such as cognitive psychology and computational neuroscience, gestalt theories of perception are criticized for being descriptive rather than explanatory in nature. For this reason, they are viewed by some as redundant or uninformative. For example, Bruce, Green & Georgeson conclude the following regarding gestalt theory's influence on the study of visual perception:
The physiological theory of the gestaltists has fallen by the wayside, leaving us with a set of descriptive principles, but without a model of perceptual processing. Indeed, some of their "laws" of perceptual organisation today sound vague and inadequate. What is meant by a "good" or "simple" shape, for example?-- Bruce, Green & Georgeson, Visual perception: Physiology, psychology and ecology
Gestalt psychologists find it is important to think of problems as a whole. Max Wertheimer considered thinking to happen in two ways: productive and reproductive.
Productive thinking is solving a problem with insight.
This is a quick insightful unplanned response to situations and environmental interaction.
Reproductive thinking is solving a problem with previous experiences and what is already known. (1945/1959).
This is a very common thinking. For example, when a person is given several segments of information, he/she deliberately examines the relationships among its parts, analyzes their purpose, concept, and totality, he/she reaches the "aha!" moment, using what is already known. Understanding in this case happens intentionally by reproductive thinking.
Another gestalt psychologist, Perkins, believes insight deals with three processes:
Views going against the gestalt psychology are:
Gestalt psychology should not be confused with the gestalt therapy of Fritz Perls, which is only peripherally linked to gestalt psychology. A strictly gestalt psychology-based therapeutic method is Gestalt Theoretical Psychotherapy, developed by the German gestalt psychologist and psychotherapist Hans-Jürgen Walter and his colleagues in Germany, Austria and Switzerland. Other countries, especially Italy, have seen similar developments.
Fuzzy-trace theory, a dual process model of memory and reasoning, was also derived from Gestalt psychology. Fuzzy-trace theory posits that we encode information into two separate traces: verbatim and gist. Information stored in verbatim is exact memory for detail (the individual parts of a pattern, for example) while information stored in gist is semantic and conceptual (what we perceive the pattern to be). The effects seen in Gestalt psychology can be attributed to the way we encode information as gist.
The gestalt laws are used in user interface design, and other design-based activities. The laws of similarity and proximity can, for example, be used as guides for placing radio buttons. They may also be used in designing computers and software for more intuitive human use. Examples include the design and layout of a desktop's shortcuts in rows and columns. In addition, Gestalt theory can also be used as a guide for creating sonic impressions while mixing audio. 
Similarities between Gestalt phenomena and quantum mechanics have been pointed out by, among others, chemist Anton Amann, who commented that "similarities between Gestalt perception and quantum mechanics are on a level of a parable" yet may give useful insight nonetheless. Physicist Elio Conte and co-workers have proposed abstract, mathematical models to describe the time dynamics of cognitive associations with mathematical tools borrowed from quantum mechanics and has discussed psychology experiments in this context. A similar approach has been suggested by physicists David Bohm, Basil Hiley and philosopher Paavo Pylkkänen with the notion that mind and matter both emerge from an "implicate order". The models involve non-commutative mathematics; such models account for situations in which the outcome of two measurements performed one after the other can depend on the order in which they are performed--a pertinent feature for psychological processes, as it is obvious that an experiment performed on a conscious person may influence the outcome of a subsequent experiment by changing the state of mind of that person.