An introductory text reads concepts are used to organize information in a manner that helps us to understand things even when we are encountering it for the first time. Formal concepts like circle, allow us to categorize the objects and ideas in a very precise way. Something either meets the criteria to be included in that category or it doesn’t. Natural concepts develop as a result of our everyday encounters and vary according to our culture and individual experiences. We tend to use prototypes, ideal representations with features we associate most with a category, to identify natural concepts.
The first panel explains a formal concept and a natural concept as follows:
Formal concept: text reads, determined by rigid precise rules. A schematic shows a circle with an arrow extending from its center. Text below reads, A circle is a two-dimensional shape in which all points are the same distance from its center.
Natural concept: text reads, Defined by general characteristics established through everyday encounters. An illustration shows the outline of a couch. Text below reads, a couch is a large piece of furniture used for sitting.
The second panel shows a flowchart which shows how concepts can be organized into hierarchies. The flowchart begins with furniture (superordinate level); it branches out into two types: couch and bed in the midlevel (basic). Couches lead to three types and beds lead to three types at the subordinate level. A text box corresponding to the subordinate level reads, Did you think of this? Maybe not. But if you are from India, the traditional charpal may be your prototype- the first image that comes in mind if someone says bed. What comes into mind if you think of the concept fruit? Researchers studying the development of categories organized in a group of items from the most prototypical to the least prototypical (Rosch and Mervis, 1975). How long would it take you to think of an olive?
The third panel shows a range of fruits from the most prototypical to the least prototypical. The fruits are shown in the following order: orange (most prototypical), apple, banana, strawberry, pineapple, lemon, date, coconut, tomato, and an olive (least prototypical).