What is Intelligence?...
Many definitions

Last updated:
30 Jul 2005

A proposed definition of intelligence

Intelligence is:

  • a ubiquitous individual difference
  • a hypothetical construct
  • reflected in a variety of behaviours which demonstrate a cognitive capacity
    • thinking and reasoning
    • learning and adapting

Also see - Student definitions of intelligence

Classic definitions of intelligence

  • "The ability to carry out abstract thinking."
    (Terman, 1921)
  • "The capacity for knowledge, and knowledge possessed."
    (Henmon, 1921)
  • "The capacity to learn or to profit by experience."
    (Dearborn, 1921)
  • "The capacity to acquire capacity."
    (Woodrow, 1921)
  • "Intelligence is what is measured by intelligence tests."
    (Boring, 1923)
  • "A global concept that involves an individual's ability to act purposefully, think rationally, and deal effectively with the environment."
    (Wechsler, 1958)
  • "Intelligence is a general factor that runs through all types of performance."
  • "A person possesses intelligence insofar as he had learned, or can learn, to adjust himself to his environment."
    (Colvin, cited in Sternberg, 1982, p.30)
  • "Intelligence is adaption to the environment."
  • "Intelligence is that faculty of mind by which order is perceived in a situation previously considered disordered."
    (R.W. Young, cited in Kurzweil, 1999)
  • "Intelligent activity consists of grasping the essentials in a given situation and responding appropriately to them."
  • "Intelligence is the ability to use optimally limited resources - including time - to achieve goals."
    (Kurzweil, 1999)
  • "Intelligence is what you do when you don't know what to do."
  • "Intelligence is a hypothetical idea which we have defined as being reflected by certain types of behaviour."