Imagine that you are looking up and you see a single bird flying in the sky. The bird is a figure, a well-defined perceptual object tending to stand out. The sky is ground (or background), the perceptual field that surrounds the figure. This is figure-ground perception. One of the features of this kind of perception is that the figure is usually smaller than the ground and tends to be seen as coming forward from the ground. Other examples include seeing a button on a blouse, a book on a table, or a car on the road.
It can be argued that this kind of perception, the ability to distinguish a figure from a field, is an inborn organizing tendency. We aren’t taught to do it. We probably start doing it spontaneously early in infancy. An infant reaching for a milk bottle suggests to us that he or she perceives the bottle as a perceptual object, a figure in a field. Figure-ground perception is probably the most fundamental organizing tendency we possess.
Keep in mind once again that perception does not necessarily reflect the structure of the world itself. For example, a word printed in black ink on a white page is perceived as slightly in front of the white surface. We are tempted to think that this is because the word is “on” the page. But imagine that a black piece of paper is covered with a stencil. The entire page is inked white, with the exception of the word. Now, from a physical point of view, the white ink is on the black surface. Nonetheless, unless carefully studied, the word, emerging in black, will be perceived as slightly forward and on the page.
Various illusions demonstrate that figure-ground perception is reversible under some conditions. The example of the word on a page and the illusions all bly suggest that figure-ground perception is a mental construction, not necessarily a fact about the physical world.
Max Wertheimer is the father of Gestalt psychology. Adding to figure-ground perception. Wertheimer proposed a set of supplemental inborn organizing tendencies, or Gestalt laws. (The Gestalt laws are also traditionally called innate tendencies, which simply means “inborn."' The words innate and inborn can be used interchangeably.)
First, proximity refers to the nearness of the elements that make up a perception.
If four ink dots on a piece of paper are arranged in the form of a square, this Gestalt (i.e., organized whole) will, of course, be perceived to be a square. Let assume that two figures are drawn. Figure A has dots that are one inch apart. Figure Б has dots that are three inches apart. Figure A will give a ber impression of being a square than will Figure Б.
When you look at stars in the sky and perceive constellations, it is because of the law of proximity. The “nearness"' of some stars to each other creates clusters that we can easily imagine to be objects such as a dipper, a hunter, or a lion.
Second, similarity refers to characteristics that elements have in common.
Let’s say that the word airplane is printed on a page in a single color of ink. Imagine that the same word is printed on a different page with its letters randomly appearing in black, red. and green. The second word is more difficult to perceive as a whole word, as a perceptual object, than is the first word. Similarity of the elements helps to make a perceptual object a coherent whole.
If a moth is dark gray and it lands on a tree with dark gray bark, it will be difficult to perceive the moth at all. This is because its similarity to the bark makes it, from a perceptual point of view, a part of the bark. However, if a light gray moth lands on the same tree, it will be easy to pick the moth out as a figure.
Third., closure is the tendency to БД in gaps in information and make a perceptual object into a complete whole. Imagine that an arc of 340 degrees is drawn on a piece of paper. Although at a sensory level this is an arc, you will tend to perceive it as a broken circle. as a coherent whole with a defect. (An unbroken circle has 360 degrees.) A newspaper photograph made up of nothing but disconnected dots is nonetheless perceived as a picture of people or things. Again, the principle of closure is at work.
Fourth, common fate exists when all of the elements of a perceptual object move or act together. (Their simultaneous activity is, in a sense, a “common fate.5! Х'СЪеп this happens, the perceptual object is quickly organized into a figure and is easily discriminated from a ground. For example, a polar bear with white fur surrounded by snow is more easily seen as a bear when it is moving than when it is stationary. Other organizing tendencies exist; however, the ones presented make clear the role that they appear to play in perception.