"Sometimes a Great Notion" is the eleventh episode in the fourth season of the reimagined Battlestar Galactica. It aired on television on Sci Fi and Space in the United States and Canada respectively on January 16, 2009 and on Sky One in the United Kingdom on January 20, 2009. This episode is the first after the mid-season finale of the fourth season ("Revelations"), which aired in June 2008. The episode title is a reference to the novel of the same name, written by Ken Kesey. The episode was also the last to be written before the 2007–2008 Writers Guild of America strike. It received a Nielsen rating of 1.6 and was received positively throughout.