No-one asks for figures to prove the worth of artistic creations; they are part of our culture and without them we lack a collective identity. At the lecture on Thurs Lessig stated that his aim was to get several million linkbacks to the Creative Commons license. Perhaps that is how we provide figures that people value freedom from excessive IP regulation. It was great to finally see Lessig speak anyway; even if they stopped us lay-men getting in to the Morgan Stanley reception at the end grrr! :)