I would like to thank Sergei Nirenburg for his continual encouragement and contributions to this work. Also appreciated are Kavi Mahesh and Evelyne Viegas for their work on the Mikrokosmos project as well as their helpful suggestions on this paper. Thanks to Remi Zajac for his thoughtful review of this material. And finally, I would also like to acknowledge and thank David Evans and Barbara DiEugenio, who, along with Sergei Nirenburg, were my advisors at Carnegie Mellon where research on an earlier version of this work was done.