Charles Spearman,Cyril Burt,and the origins of factor analysis

Cyril Burt's article on general intelligence published in the British Journal of Psychology in 1909, and to a lesser extent the correspondence of that year between Burt and Charles Spearman about the paper, have recently become one of the many areas of contention in the continuing historical evaluation of Burt and his role in the development of early factor analysis. From a detailed examination of this correspondence, we argue that Spearman's contribution to Burt's paper was both central and crucial, and confirms Spearman's priority as the originator of factor analytic methods, as they were understood at the time.