To myself a master is defined by a consensus of ones peers and the causual viewer of your work, at least in the art world and in the most part the Perl world as well. Some will never touch mastery for whatever reason... I never will. But like Data from STNG, "Becoming human isn't important as the attempt to be more than we are.".
in reply to How do you master Perl?
Mastery is it knowledge? Is it the understanding the core of the beast? Could it be something as intangable as God? Is it the ability to write a interface so simple that we are amazed?
I don't think it is merely successfulling creating a goal. I have writing things that wow 'the guys at work'. But to the larger Perl community at best crap... a hack. I am not saying I am a master nor do I desire the responsiblity/expectation that would accompany such a great and noble title. But mayhaps it is not something we can set a goal to become but happens more by chance than by skill.
So from a high standard that has been defined by those that are considered masters. A master is someone who has contributed in a significant way to perl and its larger community. And atested to that fact by the community at large. Not the code they wrote or the style it was written in, but a recognition of how they made, or though implicity made, our programming lives easier.