[Aurelius]

Anarchy is, by definition, absence of any form of political authority. Political authority implies the use of force and violence to impose mandates. There is nothing contrary to anarchist principles in forming or belonging to structured social organizations of a voluntary nature.

[AmishDude]

So, what does the 15-year-old lass do if I decide to punch her in the face 'cause I, ya know, like, feel like it, 'n stuff?

[Poincare]

Anarchism opposes authority based on pre-ordained position; it prefers authority based on performance or ability.

An-archism is a philosophy based on the opposition (an-) to established pyramidal order (archos) in favor of emergent orders of a rich textured chaos..

[AmishDude]

"Anarchist principles" -- hey you can't force your fascist principles on me, man.

Oh, alternate definitions are fun:
an·ar·chism (nr-kzm)
n.

1. The theory or doctrine that all forms of government are oppressive and undesirable and should be abolished.
2. Active resistance and terrorism against the state, as used by some anarchists.
3. Rejection of all forms of coercive control and authority: “He was inclined to anarchism; he hated system and organization and uniformity” (Bertrand Russell).

Font size changes are mine. The rest is from dictionary.com