It needs no great scientific insight to see that such multitudinously multi variate subjects as psychology, physiology, sociology, and history need multivariate methods. As this book may show, those methods-multivari ate analysis of variance, regression analysis, typal and discriminant func tion analysis, multidimensional scaling, and factor analysis-belong to a single structural arch which bears up conceptual and causal understanding in all these subjects. But factor analysis is the keystone of that arch. Since factor analysis has itself developed fantastically in thirty years my first...