Which of the following is a synonym for "subversive" as used...

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Men fear thought as they fear nothing else on earth – more than ruin, more even than death. Thought is subversive and revolutionary, destructive and terrible; thought is merciless to privilege, established institutions, and comfortable habits; thought is anarchic and lawless, indifferent to authority, careless of the well-tried wisdom of the ages. Thought looks into the pit of hell and is not afraid.

Bertrand Russell (“Why Men Fight: A Method of Abolishing the International Duel”, pp. 178-179)