Elsewhere, someone might have said, “It’s just books! Books aren’t dangerous!” But even ordinary books are dangerous, and not only the ones like Make Gelignite the Professional Way. A man sits in some museum somewhere and writes a harmless book about political economy and suddenly thousands of people who haven’t even read it are dying because the ones who did haven’t got the joke. Knowledge is dangerous, which is why governments often clamp down on people who can think thoughts above a certain caliber.