Chapter 4 takes up the enactment of the Logan Act of 1799: an act which has never been repealed and is still sometimes referred to in political contexts. The chapter examines a long speech in support of the act by Robert Harper, a leading Federalist, in December 1798. The impulse for the act came from a visit to France by Dr. Logan, a local politician from Pennsylvania, in August 1798. Dr. Logan had attempted to improve French-American relations after the official three-man delegation had failed in its mission during the preceding winter. Fallacy theory is again shown to be a useful analytical tool to shed light on the nature of Harper’s arguments in favor of the new law. For instance, it is shown that the argument from analogy is used fallaciously by Harper, who also resorted to the fallacy of the straw person. Even though Harper’s speech was very long, he failed to report what Dr. Logan had actually said to the French leaders. It is suggested that Harper’s failure to give a report of what Dr. Logan had said to French leaders was dictated by Harper’s covert goal, which was to discredit Republicans by heaping criticism on Dr. Logan’s mission.