Premise: The Warlock in Spite of Himself is a science fantasy novel by American author Christopher Stasheff, published in 1969. It is the first book in "Warlock of Gramarye" series. The title is a play on the title of Molière's "Le Médecin malgré lui" ("The Doctor, in Spite of Himself").
Hypothesis: Science fiction is Christopher Stasheff's favorite genre.