> it's a product of its time in the 1960s You might have cause and effect somewhat mixed up. SiSL came out in 1961, and he'd first started writing it in the l

> it's a product of its time in the 1960s You might have cause and effect somewhat mixed up. SiSL came out in 1961, and he'd first started writing it in the late 1940s, if I recall correctly. Heinlein's first attempt at a novel, in the 1930s (before he started writing seriously for money), has most of the tropes that define his later non-juvenile novels from the 1960s into the 1980s. It seems to me, that the attitudes of "the 60s" might have been pushed somewhat by the popularity of SiSL itself.