Essential Paul Meehl lessons to personality assessment psychology

The author presents four essential Meehl lessons for personality assessment. First, Meehl's particular form of the integration of science and practice is described. Second, by outlining Meehl's Hedonic Capacity conjecture, Meehl's contribution to the inclusion of personality individual differences in generating the full clinical picture and in planning treatment is recognized. The third Meehl lesson is on the nature and importance of theory in test development and application programs. The fourth Meehl lesson is a more general epistemological lesson for psychology. Meehl's role in destroying the fantasy of an easy methodological formula for a scientific psychology is described. His program of taxometric research is shown to be an example of demanding greater material implications from theory. Meehl's corroboration index is described and contrasted with the p value of statistical significance testing. (c) 2005 Wiley Periodicals, Inc.