Three papers--comments, a reply to comments, and a rejoinder--discussing a conclusion about the nature of general intelligence based on the size loadings of a psychomotor test of discrimination reaction time are presented. The use of Spearman's "g" is the center of the controversy. (TJH)

General intelligence may set structural feature limitations on three aspects of selective attention: direction, adjustability, and breadth. Data, theory, and methods bearing on this hypothesis were reviewed from the domain of visual discrimination learning. (Author/BW)