A fanatic is a man that does what he thinks th’ Lord wud do if He knew th’ facts iv th’ case.

This aphorism is associated with Finley Peter Dunne’s long-running “Mr. Dooley” newspaper columns, in which the Irish-American bartender Martin Dooley comments satirically on politics, religion, and public morals in a thickly phonetic brogue. Dunne wrote at the turn of the twentieth century, when American public life was marked by reform crusades, nativism, and intense moral rhetoric. In that setting, “fanatic” becomes a target for Dunne’s characteristic skepticism toward people who claim divine sanction for their certainties. The line reflects the Mr. Dooley persona’s habit of puncturing self-righteousness by treating it as a kind of presumptuous mind-reading on God’s behalf.

Dunne defines fanaticism not as mere intensity of belief but as the arrogance of assuming one’s own limited view is identical with God’s—so much so that the fanatic imagines God would agree “if He knew the facts.” The joke turns on the inversion: the human speaker positions himself as better informed than the deity, while still claiming divine endorsement. The remark exposes how zealotry often disguises itself as humility and piety, when it is really a bid for moral authority. In Mr. Dooley’s hands, the line is a warning about certainty: when people treat their opinions as heaven’s verdict, they become immune to correction, compromise, or empathy.