Categorization and its Utility

Why Categories Are Useful

• Knowing that something is in a category provides a great deal of information about it (Figure 9.1).
• Examples of cat characteristics:
  • Likes milk and fish
  • Likes to rub up against people and other objects
  • Difficult to train
  • Catches mice
  • Has whiskers
  • Sleeps a lot, but more active at night
  • A feline: related to lions and tigers
  • Meows and purrs

Definitional Approach to Categorization

• Determine category membership based on whether an object meets the definition of the category.
• This approach does not work well.
• Not all members of everyday categories have the same defining features.
• Family resemblance: Items in a category resemble one another in a number of ways.

Why Categories Are Useful

• Help to understand individual cases not previously encountered.
• "Pointers to knowledge"
• Provide a wealth of general information about an item.
• Allow us to identify the special characteristics of a particular item.