nihilism
Nihilism is popularly thought to mean "belief in nothing," but the word, as it was originally used by nineteenth-century Russian intellectuals, was meant to indicate a mistrust of any doctrine not supported by proof.
Nihilism was a reaction against the perceived corruption and artificiality of the institutions of the state. Early Nihilists were revolutionaries and anarchists, committed to the overthrow of the absolutist Russian regime.
The image of the brooding, nihilist (lower-case "n"), wearing black, skulking in coffeehouses, is an enduring caricature.