premise: Brutus de Villeroi (1794–1874) was a French engineer of the 19th century, born Brutus Amédée Villeroi (he added the aristocratic "de" in his later years) in the city of Tours and soon moved to Nantes, who developed some of the first operational submarines, and the first submarine of the United States Navy, the Alligator in 1862.
hypothesis: Brutus de Villeroi lived during the 18th and 19th centuries.
reason: Brutus de Villeroi (1794–1874) means he was born in the 18th century and didn't die until some time in the 19th century, so he lived in both. The algorithm might not understand century annotation or how someone could live in two centuries.