Whenever [I] hear any one, arguing for slavery I feel a strong impulse to see it tried on him personally.

Lincoln’s line comes from his 1854 “Fragment on Slavery,” a short private note written amid the political upheaval following the Kansas–Nebraska Act and the renewed national argument over expanding slavery into U.S. territories. In this period Lincoln was re-entering politics and sharpening the moral and logical case against slavery’s defenders. The fragment is not a public speech but a reflective memorandum in which he tests arguments he was hearing—especially claims that slavery was justified by law, property rights, or racial hierarchy—by applying a simple ethical reversal: would the advocate accept the institution if it were imposed on him?

Lincoln’s sentence is a compact moral reductio ad absurdum. Rather than arguing abstractly about property, law, or economics, he exposes what he sees as the core hypocrisy of proslavery advocacy: it depends on imagining slavery as tolerable for others while exempting oneself. By proposing that slavery be “tried” on its defenders, he reframes the issue as one of universal human vulnerability and consent, implying that no one would rationally choose enslavement. The quote also signals Lincoln’s broader approach to slavery: even when he spoke in legal and constitutional terms, he returned to a basic ethical intuition about human equality and the injustice of coercion.