the Gestalt Theory of Visual Perception

i remembered having studied this in Psychology class.. i actually enjoyed that class, whenever i attended it that is!

Gestalt is a German word meaning "organised whole", when parts identified individually have different characteristics to the whole.Parts are of secondary importance even though they can be clearly seen.
e.g. describing a tree - its parts are trunk, branches, leaves, perhaps blossoms or fruit. But when you look at an entire tree, you are not conscious of the parts, you are aware of the overall object - the tree.

The Six Principles of Gestalt Perception -

1. Proximity

   The principle of proximity or contiguity states that things which are closer together will be seen as belonging together. Looking at the picture below, since the horizontal rows of circles are closer together than the vertical columns, we perceive two vertical lines. Since the first two columns and the last two columns have less space between them than the center two columns, we perceive two groups of two columns.
   
   
   



2. Similarity

   The principle of similarity states that things which share visual characteristics such as shape, size, color, texture, value or orientation will be seen as belonging together. In the example, the two filled lines gives our eyes the impression of two horizontal lines, even though all the circles are equidistant from each other.
   
   
   



3. Good Continuation

   The principle of continuity predicts the preference for continuous figures. We perceive the figure as two crossed lines instead of 4 lines meeting at the center.
   
   
   



4. Closure

   The principle of closure applies when we tend to see complete figures even when part of the information is missing. Our minds react to patterns that are familiar, even though we often receive incomplete information. Even though the circle is not joined together, we still perceive a circle due to the principle of closure.
   
   
   



5. Figure & Ground

   The terms figure and ground explain how we use elements of the scene which are similar in appearance and shape and group them together as a whole. Similar elements (figure) are contrasted with dissimilar elements (ground) to give the impression of a whole. In the picture, the lighthouse stands out as the figure, while the horizontal blue lines are perceived as ground.
   
   
   



6. Area & Symmetry

   The principle of area states that the smaller of two overlapping figures is perceived as figure while the larger is regarded as ground. We perceive the smaller square to be a shape on top of the other figure, as opposed to a hole in the larger shape.
   
   
   
   
   
   The principle of symmetry describes the instance where the whole of a figure is perceived rather than the individual parts which make up the figure. What do you see in the figure below? Two overlapping diamonds, or three objects, a small diamond and two irregular objects above and below it? If you are perceiving according to the principle of symmetry, you will probably see two diamonds overlapping.