The classification of knowledge – Raimundus Lullus' “Tree of Knowledge” in the official CAS emblem
From the trees of paradise to the genealogical tables of the nobility, from Porphyry's classification schema (Porphyrian tree) to the trees of knowledge from the early modern age and their newest offshoots in genetics and computer science, the tree is central to western iconography. Its form vividly represents the most varied types of temporal or causal relationships. "Genealogical trees were a source of order for the world," writes cultural historian Thomas Macho, "on the one hand, because they gave the world a temporal backbone, and on the other, because they tried to hierarchically differentiate the genera and classes of being." Since the Tree of Knowledge in the Garden of Eden, no matter how much diversity of form there has been, one field of significance has always been central, namely: knowledge. How can it be classified, how do the various fields of knowledge fit together and how can newly discovered areas of knowledge be understood using existing schemata?
The Center for Advanced Studies is now adopting the tree of knowledge found in the works of Catalan philosopher Raimundus Lullus (1232-1316) for its emblem. In his "Ars magna", Lullus had previously developed a mechanism designed to categorize the entire system of the sciences by means of a series of basic terms and their combination. To do this, he used various new representational methods such as concentric arrangements of segments of a circle or combinations of geometric figures that could be rotated or moved towards or against each other. In his extensive work "Arbor scientiae", published in 1295, he assumed the widely known form of the tree of knowledge in order to make his Ars easier to understand. To be somewhat more precise, this work – as historian Frances A. Yates also formulates it – covers an entire forest of knowledge. Not only does it consist of a single tree, but of sixteen individual trees, each of which systematically categorizes individual areas of knowledge. In their shared identity, however, these trees represent the totality of knowledge – God and man, nature, art and science. The singular use of the word 'Arbor' in the title of the work, however, indicates its underlying concept of unity.