The thesis of this article is that the multitude of procedures for testing hypotheses about mean contrasts often presented in statistical methods textbooks is seemingly unwarranted. Nearly all research situations calling for the study of contrasts can be handled with a single contrast test statistic, that often attributed to R. A. Fisher. By jointly considering a probability value and an eta-squared value and by keeping in mind the total number of contrasts studied, one finds that a single contrast test procedure evolves.
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