Porphyrian tree

The Tree of Knowledge is a classic epistemological order system, borrowed from the botanical semantics. It goes back to the Platonic Dihairesis, based on both the Aristotelian categories as well as the Isagoge of Porphyry of Tyre. The translator and commentator Boëthius visualized the system for the first time in the 6th century as a tree, and Peter Hispanus it introduced in 1240 under the name Porphyrianischer Tree ( Arbor porphyriana ) in scientific history.

Comparable structures are several late antique and medieval encyclopaedias based about Ramon Llull's Arbor scientiae (1295 ) or the Theatrum Humanae vitae Theodor Zwinger, 1565th The well of Francis Bacon ( 1561-1626 ) recorded metaphor was last used by Diderot in the Encyclopédie, where showed limits of their usefulness.

Tree of science Descartes called the great book of the world, the totality of knowledge and science.

Before the tree metaphor knowledge was understood as a circular to arrange, see Seven Liberal Arts.

The tree as a metaphor disposition

A) Arbor porphyrii in Purchotius ' Institutiones philosophicae I, 1730 (detail a) b ) Arbor porphyrii probably from a Boethius translation (detail b ) c ) Tree of Ramon Llull's Ars generalis ultima 1305 authored, published after 1500 ( detail c ) d) Ramon Llull 16teilige Arbor scientiae (about 1295) in a woodcut from 1505 ( detail d ) e) Denis Diderot 1751: Figurative illustrated system the knowledge of man. Flyleaf, Volume 1 of the Encyclopédie (Detail e, 313k, or German translation, 300k ) f) The same system represented in tree form, reaches the limit of usefulness ( Etching from 1769, 985x635 mm, flyleaf, Vol 1 of the register Encyclopédie, 1780) (detail f)

Arbor porphyriana

The Arbor porphyriana (also porphyrii arbor, arbor de Porfirio, Tree of Porphyry term or pyramid) is introduced in the history of science by the scholastics Peter Hispanus 1240 metaphor.

It is based on a classification method, which Porphyry of Tyre ( * ca 233 AD; † about 303 ) had in his Isagoge above ( an introduction to the font categories of Aristotle ). As Porphyry's philosophical system of five basic concepts ( predicables ) to each other, it is also known as Quinque voces ( " Of the five Lautungen "; " five words" ). The schema of the tree of Porphyry allows Subordinierung of genus and species- can be classified into the real genera and species. The ten possible relationships between the five predicables comply with its ten categories of Aristotle, see Figure

The respective highest genus ( the summum genus) of such a tree is the category. It determines the highest level of abstraction. In contrast to underlying layers, the highest genus not be kind to another. A lowest kind ( infima species) can not be further divided, in contrast to the parent levels. It is an individual concept. All layers in between are both kind of the next higher level and genus ( proximum genus) of the next lower.

The term pyramid of concepts refers to the gradation of the terms between the top and bottom. Since each " highest class " always lots of style or summarizing sub-concepts in itself, the content richness of the concepts from above increases down more and more. Conversely arise from bottom to top of ever more extensive additional terms, see → extension and intension. Unclear, however, remains whether the head of such a concept pyramid would not have to lead to the most general and most comprehensive of all the concepts about the being or the One or if there is an interdependence ( συμπλοκή ) a plurality of top generic terms, as Plato advocated ( " upper closure problem " ).

Arbor scientiae

Arbor scientiae is an encyclopedia of the Catalan Ramon Llull ( Raymond Lully ) in which, as in many advanced medieval encyclopaedias the tree allegory is used to systematize the sciences: L' arbre de Ciència was written in 1295 in Catalan, but not until 1482 published - in Latin.

In the Arbor scientiae the (partial ) represent trees fourteen realms ( elements, botany, animals, sensation, imagination, morality, society, teaching ... ), which are illustrated by two other trees examples ( exempla ) and proverbs ( bons mots ).

9 Arbor caelestialis (D) Arbor 10 angeli calis (C ) 11 Arbor aeviternitalis ( " tree of eternal life" ) 12 Arbor maternalis 13 Arbor Jesus Christ 14 Arbor divinalis (B ) ( "Tree of God " ) 15 Arbor exemplificalis 16 Arbor quaestionalis ( " tree of questions " )

In the written Ars generalis ultima 1305 Llull again engages the tree structure of the Arbor porphyrii (Figure c ) to expand and develop his logical apparatus.

The scheme of human knowledge in the " Encyclopédie "

With the systems figuré of connoissances humaines ( German translation, image ) Denis Diderot Encyclopédie as structured his last major encyclopedia on the basis of a "Tree of Knowledge" in the manner of Francis Bacon. At several important places Diderot deviates from this value; his Encyclopedia thus initiates an epistemological change of direction [ a ] who transformed the topography of all human knowledge ( Darnton ).


In modern times, the traditional classification system has been questioned fundamental:

  • Ludwig Wittgenstein demonstrated the impossibility of a hierarchical classification of certain categories and introduced as an alternative the notion of family resemblance.
  • The philosopher Michel Foucault presents in The Order of Things (1974 ) any category systems in question, since they are subject to space-time bondage; he shows in his archeology of knowledge that each category system acts arbitrarily when it is viewed from an external perspective (see Taxonomy ).
  • More postmodern criticism that Deleuze and Guattari, who introduced the rhizome as a metaphor knowledge.
  • And the network is referred to in this context.