I feel like one of the most important theoretical terms in classical anarchist theory is the concept of "justified hierarchy" that Bakunin talked about in "What is Authority?". One of the most outrageous sounding parts of anarchy for the newcomer who is down with abolishing the state and capitalism seems to often be talking about how anarchy would mean the abolition of all hierachy. One would then ask how that could possibly happen when there will always be some people who know more about things than other people and therefore have "authority" over them as an "authority" on the topic. And surely anyone who is interested in doing anything they don't know how to do - just to carry on with this example since it's what Bakunin talks about with the bootmaker and the apprentice - will listen to what an "authority" on a topic has to say.
I happen to think nevertheless that the concept of justified authority is a really weak one, and strays dangerously close to being yet another example of the inherent liberalism in classical anarchism. What sorts of criteria would we cash out for when authority is justified? Bakunin says that the apprentice may listen to the bootmaker on the topic of how to make boots, but will not allow the bootmaker to coerce/dominate them just because they know more about some particular topic. But in this example of being a craftsman - or any kind of profession - there are always going to be new ways of doing things and old timers who are stuck in how they think things should be done. One might argue that it's necessary for young, rebellious apprentices with a fresh insight to disobey the advice of their teachers if progress will ever be made in any field, craft or art or science or whatever.
This just makes me wonder whether or not post-left anarchy has an answer to the question of justified hierarchy, or what any of you think about how one could critique the idea of justified hierarchy.