In 1910, psychologist Max Wertheimer had an insight when he observed a series of lights flashing on and off at a railroad crossing. It was similar to how the lights encircling a movie theater marquee flash on and off. To the observer, it appears as if a single light moves around the marquee, traveling from bulb to bulb, when in reality it’s a series of bulbs turning on and off and the lights don’t move it all. This observation led to a set of descriptive principles about how we visually perceive objects. These principles sit at the heart of nearly everything we do graphically as designers.
The whole is other than the sum of the parts.
Gestalt principles, or gestalt laws, are rules of the organization of perceptual scenes. When we look at the world, we usually perceive complex scenes composed of many groups of objects on some background, with the objects themselves consisting of parts, which may be composed of smaller parts, etc. How do we accomplish such a remarkable perceptual achievement, given that the visual input is, in a sense, just a spatial distribution of variously colored individual points? The beginnings and the direction of an answer were provided by a group of researchers early in the twentieth century, known as Gestalt psychologists. Gestalt is a German word meaning 'shape' or 'form'. Gestalt principles aim to formulate the regularities according to which the perceptual input is organized into unitary forms, also referred to as (sub)wholes, groups, groupings, or Gestalten (the plural form of Gestalt). These principles mainly apply to vision, but there are also analogous aspects in auditory and somatosensory perception. In visual perception, such forms are the regions of the visual field whose portions are perceived as grouped or joined together, and are thus segregated from the rest of the visual field. The Gestalt principles were introduced in a seminal paper by Wertheimer (1923/1938), and were further developed by Köhler (1929), Koffka (1935), and Metzger (1936/2006; Todorović, 2007).
- Emergence (the whole is identified before the parts)
Emergence is the process of forming complex patterns from simple rules. When attempting to identify an object, we first seek to identify its outline. We then match this outline pattern against shapes and objects we already know to find a match. Only after the whole emerges through this outline pattern matching, do we start to identify the parts that make up the whole. When designing, keep in mind that people will identify elements first by their general form. A simple well defined object will communicate more quickly than a detailed object with a hard to recognize contour.
- Reification (our mind fills in the gaps)
Reification is an aspect of perception in which the object as perceived contains more spatial information than what is actually present. As we attempt to match what we see to the familiar patterns we have stored in memory, there isn’t always an exact match. Instead we find a near match and then fill in the gaps of what we think we should see. Reification suggests that we don’t need to present the complete outline in order of viewers to see it. We can leave out parts of the outline as long as we provide enough of it to allow for a close enough pattern match.
In the left image above, you should see a white triangle even though the image is actually comprised of three black Pac-Man-like shapes. On the right image, you see a panda even though the figure is several random shapes. Seeing the triangle and panda is simpler than trying to make sense of the individual parts.It’s about the human tendency to seek and find patterns.
- Multi-stability (the mind seeks to avoid uncertainty)
Multi-stability is the tendency of ambiguous perceptual experiences to move unstably back and forth between alternative interpretations. Some objects can be perceived in more than one way.
The figure/ground relationship can be either stable or unstable depending on how easy it is to determine which is which. The classic example of where the relationship is unstable is the left image above. You either see a vase or two faces depending on whether you see the black color as figure and the white as ground, or vice versa. That you can easily bounce back and forth between the two perceptions demonstrates the unstable relationship.
The more stable the relationship, the better we can lead our audience to focus on what we want them to see.
Two related principles can help us:
a.) Area The smaller of two overlapping objects is seen as figure. The larger is seen as ground. You can see this in the right image above. The smaller shape is the figure regardless of color.
b.) Convexity Convex rather than concave patterns tend to be perceived as figures.
"Elements with a point of interest, emphasis or difference will capture and hold the viewer’s attention."
This principle suggests that our attention will be drawn toward contrast, toward the element that is unlike the others in some way. In the image below, your eye should be drawn to the square. It’s a different shape and color from the other elements. I’ve also given it a drop shadow to further emphasize it.
The principle of focal points likely arises out of our need to quickly identify the unknown to alert us to potential danger. The principles of similarity and focal points are connected, and focal points can’t be seen without the presence of similarity among other elements.
- Past Experiences
"Elements tend to be perceived according to an observer’s past experience."
Past experience is perhaps the weakest gestalt principle. In conjunction with any of the other principles, the other principle will dominate over the past experience principle. Past experience is unique to the individual, so it’s difficult to make assumptions about how it will be perceived. However, there are common experiences we all share. For example, a lot of color meaning arises out of past experience.
Having seen traffic lights throughout our lives, we expect red to mean stop and green to mean go. You probably see the image above as a traffic light on its side, because of the three common colors. That’s past experience at work. Many of our common experiences also tend to be cultural. Color again provides examples. In some countries, white is seen as pure and innocent and black as evil and death. In other countries, these interpretations are reversed. Conventions can arise when the experience is commonly shared, though again it’s important to remember that we don’t all share the same experiences.
All the above principles are well established and the least explored of them is the Past Experiences. This would require data which then needs to be converted into contextual information before applying the principle to organize the visual design of a Structure. We will be formulating a system/build science in due course to make educated design decisions using these principles.