BINGO!

Of course, there are exceptions. You can do this with certain creative commons and open source licenses, because the author gave you permission to (through the license they offered it under). You can also do so with works where the author granted you permission through other means (e.g. directly) or for works that have fallen into the public domain. Since modern copyright terms ensure that the author is both dead and most thoroughly decomposed, the moral imperative to compensate the author is gone.

You can also share knowledge derived from a work under restrictive copyright terms, but doing so requires creating a work of your own. That means that you have to do a lot more than editing. It may seem like splitting hairs, but it isn't. Freedom demands the free exchange of knowledge, so you are free to steal someone else's ideas. Freedom does not necessitate stealing someone else's words, so you are not allowed to do so.