In March 1804, at a dinner, Hamilton spoke of Burr as a dangerous man with two men named Cooper and Tayler. Afterwards, Cooper wrote a letter to a friend, describing the conversation. Excerpts from the letter appeared in the Post, and Cooper claimed the letter had been stolen. Cooper would later say that he had been circumspect in his letter and had not written the specific details of a “still more despicable opinion” (800) that Hamilton had voiced against Burr. It was this despicable opinion that drove Burr to send a letter to Hamilton, demanding an explanation for the despicable act he alluded to. 

Hamilton would not retract his statement, because he protested that he did not know what remark “despicable” might have referred to. He asked Burr for greater clarification, and stated that he could only disavow or apologize for specific comments if he knew what they were.

After a great deal of writing back and forth to each other, the duel was scheduled. Hamilton, given his “avowed opposition to dueling” (806), planned on firing his pistol, but missing intentionally, just as he had encouraged Philip to do in his duel with Eacker. Hamilton did not prepare for the duel, but there was evidence that Burr had been practicing with pistols for months.