A failure to appreciate this distinction is responsible for many lame performances in our public controversies. The effects are, in outline, that the dialectician cannot understand why his demonstration does not win converts; and the rhetorician cannot understand why his appeal is rejected as specious. The answer, as we have begun to indicate, is that the dialectic has not made reference to reality, which men confronted with problems of conduct require; and the rhetorician has not searched the grounds of the position on which he has perhaps spent much eloquence. True, the dialectician and the rhetorician are often one man, and the two processes may not lie apart in his work; but no student of the art of argumentation can doubt that some extraordinary confusions would be prevented by a knowledge of the theory of this distinction. Beyond this, representative government would receive a tonic effect from any improvement of the ability of an electorate to distinguish logical positions from the detail of rhetorical amplification. The British, through their custom of putting questions to public speakers and to officers of government in Parliament, probably come nearest to getting some dialectical clarification from their public figures. In the United States, where there is no such custom, it is up to each disputant to force the other to reveal his grounds; and this, in the ardor of shoring up his own position rhetorically, he often fails to do with any thoroughness. It should therefore be profitable to try the kind of analysis we have explained upon some celebrated public controversy, with the object of showing how such grasp of rhetorical theory could have made the issues clearer. For this purpose, it would be hard to think of a better example than the Scopes “evolution” trial of a generation ago. There is no denying that this trial had many aspects of the farcical, and it might seem at first glance not serious enough to warrant this type of examination. Yet at the time it was considered serious enough to draw the most celebrated trial lawyers of the country, as well as some of the most eminent scientists; moreover, after one has cut through the sensationalism with which journalism and a few of the principals clothed the encounter, one finds a unique alignment of dialectical and rhetorical positions. The background of the trial can be narrated briefly. On March 21, 1925, the state of Tennessee passed a law forbidding the teaching of the theory of evolution in publicly supported schools. The language of the law was as follows: