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Current Version - Under Revision

A concept definition has one of the following two forms:

  1. fully defined


    • The definition is complete. It contains


      that represent the full set of necessary and sufficient conditions.
  2. primitive


    • The definition is incomplete. It contains


      that represent a set of necessary conditions but this set of conditions is not sufficient to fully define the


Note: A necessary condition is a characteristic that is always true of a concept
Example: |morphology| = |fracture| is a necessary condition of |fracture of femur|
Note: If all members of a sufficient set of conditions are true they imply that the concept is also true.
Example: |morphology| = |fracture| and |finding site| = |bone structure of femur| form a sufficient set of conditions that define the concept |fracture of femur|
Note: All members of the set of sufficient conditions are also necessary conditions. However, some necessary conditions may not form part of the sufficient set of conditions.
Consider the concept |gastric ulcer|