Birth of a Notion is a Looney Tunes cartoon animated in 1946 and released in 1947. It was reissued as a Blue Ribbon Merrie Melodies cartoon, with the ending theme song still being that of the Looney Tunes cartoon. It features Daffy Duck, as well as a dog named Leopold and an unnamed mad scientist. Director Robert McKimson used his "Barnyard Dawg" character design as Leopold, while the scientist is a caricature, both visually and vocally, of Peter Lorre. The title is a play on The Birth of a Nation, but there is no other connection to that 1915 film.