The contention of this paper is that logicality and emotionality are not two poles of a continuum but orthogonal dimensions which may exist to varying degrees in an argument. It was hypothesized that: (1) logicality and emotionality would be perceived as independent components by subject; and (2) messages high in logic would have more influence on attitudes than messages low in logic. In a series of eight experiments, the two dimensions were objectively manipulated within written essays in a 2x2 ANOVA design. Subjects (an average of 67 per experiment) were undergraduates at a small midwestern college. Subjects' ratings confirmed the subjective independence of the dimensions. Attitude change as a function of high/low logicality and/or emotionality was also examined. While emotionality had no effect, there was a weak but consistent effect for logicality; but even the reading of illogical essays resulted in attitudes significantly different from those of a control group. One figure and one table of data are included. Twenty-four references are attached. (Author/SR)