"Ninety percent of everything is crap".
В оригинальной формулировке:
"When people talk about the mystery novel, they mention The Maltese Falcon and The Big Sleep. When they talk about the western, they say there's The Way West and Shane. But when they talk about science fiction, they call it 'that Buck Rogers stuff,' and they say 'ninety percent of science fiction is crud.' Well, they're right. Ninety percent of science fiction is crud. But then ninety percent of everything is crud, and it's the ten percent that isn't crud that is important. and the ten percent of science fiction that isn't crud is as good as or better than anything being written anywhere."
В современной формулировке как-то лучше и жизненней. На уровне закона Мэрфи :-)
P.S. Этот закон Старджона пришел на смену его же прежнему закону: «Nothing is always absolutely so». Тоже неплохо так.