“…an inborn or innate quality, as distinct from abilities acquired through individual experience…” Encyclopaedia Britannica
“…capacity to act purposefully, think rationally and deal purposefully with the environment” D Welsher
“Innate general cognitive ability” Cyril Burt
“ …an innate quality, as distinct from abilities acquired through learning.” Herbert Spencer
“…is the equipment which enables us first to understand and then to solve, problems” Erwin Brecher
“The theory of Structural Cognitive Modifiability describes intelligence as “the unique propensity of human beings to change or modify the structure of their cognitive functioning to adapt to the changing demands of a life situation.”” Reuven Feuerstein
“To my mind, a human intellectual competence must entail a set of skills of problem solving – enabling the individual to resolve genuine problems or difficulties that he or she encounters and, when appropriate, to create an effective product – and must also entail the potential for finding or creating problems – and thereby laying the groundwork for the acquisition of new knowledge.” Howard Gardener
“Judgment, otherwise called “good sense,” “practical sense,” “initiative,” the faculty of adapting one’s self to circumstances … auto-critique.” Alfred Binet
Of course there are more, but I think that is a reasonably representative sample.
I would like to see the definition of intelligence condensed and tightened up. I intend to do that.