In 1911, he moved to the University of Giessen, where he taught till 1927. While there, he wrote Growth of the Mind: An Introduction to Child Psychology (1921). In
He wrote an article for Psychological Bulletin which introduced the Gestalt program to readers in the U.S.
In 1927, he left for the U.S. to teach at Smith College. He published Principles of Gestalt Psychology in 1935. He died in 1941.
The Theory
Gestalt psychology is based on the observation that we often experience things that are not a part of our simple sensations. The original observation was Wertheim-er's, when he noted that we perceive motion where there is nothing more than a rapid sequence of individual sensory events. This is what he saw in the toy stroboscope he bought at the Frankfurt train station, and what he saw in his laboratory when he experimented with lights flashing in rapid succession. The effect is called the phi phenomenon, and it is actually the basic principle of motion pictures.
If we see what is not there, what is it that we are seeing? You could call it an illusion, but its not an hallucination. Wetheimer explained that you are seeing an effect of the whole event, not contained in the sum of the parts. We see a coursing string of lights, even though only one light lights at a time, because the whole event contains relationships among the individual lights that we experience as well.
Furthermore, say the Gestalt psychologists, we are built to experience the structured whole as well as the individual sensations. And not only do we have the ability to do so, we have a strong tendency to do so. We even add structure to events which do not have gestalt structural qualities.
In perception, there are many organizing principles called gestalt laws. The most general version is called the law of pragnanz. Pragnanz is German for pregnant, but in the sense of pregnant with meaning, rather than pregnant with child. This law says that we are innately driven to experience things in as good a gestalt as possible. Good can mean many things here, such a regular, orderly, simplicity, symmetry, and so on, which then refer to specific gestalt laws.
For example, a set of dots outlining the shape of a star is likely to be perceived as a star, not as a set of dots. We tend to complete the figure, make it the way it should* be, finish it. Like we somehow manage to see this as a B...
The law of closure says that, if something is missing in an otherwise complete figure, we will tend to add it. A triangle, for example, with a small part of its edge missing, will still be seen as a triangle. We will close the gap.
The law of similarity says that we will tend to group similar items together, to see them as forming a gestalt, within a larger form. Here is a simple typographic example:
OXXXXXXXXXX
XOXXXXXXXXX
XXOXXXXXXXX
XXXOXXXXXXX
XXXXOXXXXXX
|
|
|
XXXXXOXXXXX
XXXXXXOXXXX
XXXXXXXOXXX
XXXXXXXXOXX
XXXXXXXXXOX
XXXXXXXXXXO
It is just natural for us to see the o's as a line within a field of x's.
Another law is the law of proximity. Things that are close together as seen as belonging together. For example...
************** ************** **************
You are much more likely to see three lines of close-together *'s than 14 vertical collections of 3 *'s each.
Next, there's the law of symmetry. Take a look at this example:
[][][]
Despite the pressure of proximity to group the brackets nearest each other together, symmetry overwhelms our perception and makes us see them as pairs of symmetrical brackets.
Another law is the law of continuity. When we can see a line, for example, as continuing through another line, rather than stopping and starting, we will do so, as in this example, which we see as composed of two lines, not as a combination of two angles...:
