Recent work on the biological basis of intelligence has forced psychol
ogists to reconsider the definition and conceptualization of ''intelli
gence'' widely accepted during the last fifty years. Work with the ele
ctroencephalograph, the averaged evoked potential, reaction time and o
ther largely physiological and non-cognitive measures has resurrected
the conception of intelligence which originated with Sir Francis Galto
n, and has posed great problems for the conceptualization beginning wi
th A. Binet, and still widely accepted.