Research on facial expressions of emotion has been episodic. The topic flourished from 1920 to 1940, drawing the attention of well-known psychologists, e.g., Allport, Boring, Goodenough, Guilford, Hunt, Klineberg, Landis, Munn, Titchener, and Woodworth. However, the cumulative knowledge was unimpressive. In the opinion of influential reviewers (Bruner & Tagiuri, 1954; Hunt, 1941; Tagiuri, 1968), there were no consistent answers to the most fundamental questions about the accuracy of information provided by facial expressions, their universality and possible innateness, etc. During the next 20 years there were comparatively few studies of facial expression, with the exception of Schlosberg's reports (Schlosberg, 1941, 1952, 1954) that categorical judgments of emotion could be ordered in terms of underlying dimensions.