In psychology, concepts can be divided into two categories: natural and artificial. Natural concepts are formed through direct or indirect experiences. For example, consider the concept of snow. If you live in a place with regular snowfall, such as Essex Junction, Vermont, you know snow through direct experiences. You’ve seen it fall, touched it, shoveled it, and played in it. You recognize its texture, appearance, and even its smell. In contrast, if you live on an island like Saint Vincent in the Caribbean, where snow is uncommon, you might know snow only through indirect experiences, such as seeing pictures, watching films, or reading descriptions. Regardless of how you learn about it, your understanding of snow is constructed through observations and experiences.

Artificial concepts, on the other hand, are defined by specific sets of characteristics, and, unlike natural concepts, are not defined by experience and are true regardless of experience. Geometric shapes serve as good examples. A triangle always has three angles and three sides, while a square always has four equal sides and four right angles. Mathematical formulas, such as the equation for the area of a rectangle (length × width), are also artificial concepts because unchanging characteristics define them. These concepts are essential for building and understanding more complex ideas needed for advanced problem-solving and reasoning. For instance, to understand the area of a square, you must first understand what a square is. This foundational knowledge enables you to learn about the area of more intricate geometric shapes.

Artificial concepts are crucial for effective communication and complex thought processes. Goldstone and Kersten suggest that artificial and natural concepts act as building blocks that can be combined in numerous ways to create complex ideas and develop complex thoughts.