Birth of a Notion is a 1947 Warner Bros. Looney Tunes cartoon directed by Bob Clampett and Robert McKimson. The cartoon was released on April 12, 1947, and stars Daffy Duck.Director McKimson uses his "Barnyard Dawg" character design as Leopold, the mad scientist's dog, 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.

Birth of a Notion is one of three shorts that had been scheduled for direction by Bob Clampett before he left Warner Bros. Cartoons; the other two were Bacall to Arms and The Goofy Gophers, both of which were finished by Arthur Davis. Mel Blanc voiced Daffy Duck, Leopold and Joe Besser Duck, while an uncredited Stan Freberg voiced the mad scientist.