When Larry Lessig came up with the idea for the Creative Commons, he intended to create an alternative licensing system that would solve copyright registration problems in the United States. While admirable, the idea in many respects serves to enshrine the current copyright regime as a monarchy and forces us to accommodate that system. This is because Creative Commons copyrights start with a creator being vested with the full rights, powers, and privileges gained by virtue of the existing copyright laws, and then voluntarily divesting himself of some of those rights and privileges — a winnowing away — to grant the end-users a license that is less restrictive than that imposed by the current iteration of the Copyright Act.
The Creative Commons project as has been lauded as Open Source for artists, since all creation is built on a foundation of what came before. And if everything that came before is locked up for 70 years after the death of its creator then it hampers the ability of our modern poets, novelists, musicians and artists from using any of their predecessors’ work for a period which encompasses almost their entire lifetimes. The Creative Commons alternative frees us from those restrictions a bit, letting more artists offer their work to be used by others on such liberal terms as “free,” or “free, with attribution,” or “free, but not for commercial use.” Indeed, if you can think of a situation in which a bundle of rights is granted to the public in connection with a work, then you can probably find a Creative Commons license somewhere that fits it.
The Creative Commons movement closely relates to the Copyleft movement, which grants a free license for use on the condition that all derivative works remain free as well (i.e., if you use my stuff for free, then your stuff has to be free too). The idea behind the movements centers on the notion that the public has a paramount interest in access to knowledge and the ability to use that knowledge to further the interests of humanity. While this may smack of protectionism, the notion of the Commons is as old as our society, and is the reason we still have such things as Golden Gate Park, Yellowstone, the Grand Canyon, the Appalachian Trial, public beaches, the National Museum, and other public treasures. The Commons includes things that are deemed to be ours as a people, and that cannot and should not be appropriated by any person for their own personal use and profit. As with parks, the broad category of human knowledge has long been held to belong to us, and not to any corporate entity or oligarch. Thus, you can go to your public library and teach yourself physics from Newtonian first principles (in theory, assuming your library is open anymore), or you can do the same thing online with texts that are in the public domain or through an Open Learning course (like the edX program jointly sponsored by Harvard and MIT).
You might ask why a more relaxed copyright scheme is preferable to what we currently have, since we seem to muddle along well enough with things as they are. Art is being created, after all, books are still being written, choreographers are still indulging their fantasies of becoming the next Martha Graham — so why does Creative Commons matter? The answer to that lies in the question itself — i.e., why should we just muddle along? Why should we change the copyright laws in a way that serves corporate interests at the expense of artists? When the latest copyright scheme — the Sonny Bono Copyright Extension Act (famously known as the Mickey Mouse Protection Act) — was pushed through Congress and extended copyright protections for an additional 20 years, the reaction in the intellectual property community was a resounding “What??!!! Are you kidding me??” Copyright was originally intended to last just 14 years, as an incentive for artists to continue to create, but of late it has grown interminable. Its tentacles have stretched until we are forced to bow to such monstrous notions as The Happy Birthday Song being protected by copyright almost 100 years after its creation, generating $2MM annually for the heirs of the heirs of the heirs of the original creator. Our current copyright laws are not a tool for enabling the transmission of knowledge, or an incentive to spark creative genius, but a weapon to extract fees from users and stifle creativity itself. In a world where 500 years ago the poets already lamented that there was nothing new under the sun, narrowing their rights to exercise poetic license seems absurd.
What Creative Commons attempts to do is loosen the stranglehold on copyright, and give artists some measure of access to works created in our current age without being crippled by licensing fees or falling prey to infringement lawsuits for sampling a few bars of music. It seeks to expand the realm of knowledge, rather than limit it. While it may just be a stepping stone to progress, rather than the real progress many of us would like to see (i.e., a modification of existing laws), it is an improvement nonetheless.