There is always need of persons not only to discover new truths, and point out when what were once truths are true no longer, but also to commence new practices, and set the example of more enlightened conduct. The past provides many instances where the law refused to see a human being when it should have. . . . The challenge for future generations will be to define what is most essentially human. The extension of the Common Benefits Clause to acknowledge [same-sex couples] as Vermonters who seek nothing more, nor less, than legal protection and security for their avowed commitment to an intimate and lasting human relationship is simply, when all is said and done, a recognition of our common humanity.