In 1956, Heinlein wrote The Door into Summer, an adult novel about time travel that ranked with his best work, and Citizen of the Galaxy, a juvenile about a young slave who becomes a spy. Campbell rejected the former, but bought the latter, taking the opportunity to share a few thoughts on the institution of slavery itself. Dalgliesh, in turn, worried that its treatment of religion would pose problems for book publication, causing Heinlein to recoil more than usual: “Two changes, admittedly easy and unimportant, threw me into [a] spin and lost me ten days’ working time.”
