Klassifikation und andere Ordnungssysteme


 1. Introduction
 2. Why ordering systems should be of interest to the philosopher?
 3. The universality of diversity
 4. Objectives of ordering systems
 4.1. Sorting
 4.2. Information storage and retrieval is a major objective of most ordering systems 
 4.3. Identification of an unknown item 
 4.4. Inferences about not yet studied properties
 4.5. To serve as base line in comparative studies 
 5. Kinds of Ordering Systems
 5.1 General considerations 
 5.2. Ordering of single entities 
 5.2.1. Assigning singular entities to a linear sequence (sequential listing) –type 1 
 5.2.1.1. Arbitrary sequence 
 5.2.1.2. Alphabetical listing 
 5.2.1.3. Chronological listing 
 5.2.1.4. Listing by rank or achievement 
 5.2.2. Ordering the chemical elements according to numerical properties of their atoms – type 2 
 6. Ordering by the clustering of entities 
 6.1. Ordering by a single criterion 
 6.2. Ordering by special similarity – type 3
 6.2.1. Establishing groups by logical division (mostly dichotomy = ‘‘downward classification’’) 
 6.2.2. Special purpose ordering 
 6.3. Arrangement of entities into classes based on overall (comprehensive) similarity– type 4 
 6.4. Ordering by phylogeny or by similarity and phylogeny – types 5 and 6 
 7. Evolution versus phylogeny
 7.1 Darwinian evolution 
 7.2. Haeckelian phylogeny 
 7.3. Hennigian phylogeny 
 8. Class and classification
 8.1. Definition of class 
 8.2. Construction of classes (taxa) 
 8.3. General definition of classification 
 8.4. Biological classifications as hierarchies 
 8.5. Ranking 
 9. Similarity
 9.1. General concept and use in classification 
 9.2. Meaning of similarity in biological classification 
 9.3. How to determine similarity? 
 9.4. Overall similarity 
 9.5. Sources of similarity in organisms 
 9.5.1. Evidently descended from the same ancestor 
 9.5.2. Parallelophyly 
 9.5.3. Reversal 
 9.5.4. Convergence 
 9.6. Significance of characters (weighing) 
 9.7. Numerical approaches 
 10. Ordering by using only the criterion of phylogeny – type 5
 10.1. Hennigian cladification 
 10.2. Peculiarities of Hennigian terminology 
 10.2.1. Paraphyly 
 10.2.2. Monophyly 
 10.2.3. Relationship 
 10.2.4. Classification 
 10.2.5. Taxon 
 10.3. Cladistic analysis 
 10.4. Recognition of clades 
 11. Upward classification by two criteria, clustering by similarity and by common descent – type 6
 11.1. Pre‐Darwinian classification 
 11.2. Post‐Darwinian classification 
 11.3. Genealogy alone does not give a classification 
 11.4. Is a biological classification a theory? 
 12. Ecological factors of evolution and classification
 12.1. The origin of a new higher taxon (splitting or budding) 
 12.2. Impact of ecological shifts on classification 
 13. Phylogenetic or genealogical analysis
 13.1. Use in biological classifications 
 13.2. Translating the phylogenetic analysis into an ordering system 
 13.2.1. Darwinian classification 
 13.2.2. Hennigian cladification 
 14. Graphic representations of ordering systems 
 14.1. Phenogram 
 14.2. Haeckelian‐Darwinian dendrogram 
 14.3. Hennigian cladogram 
 15. Darwinian classification or Hennigian cladification? 
 15.1. Merits and deficiencies of Darwinian classification
 15.1.1. Classification 
 15.1.2. Phylogeny 
 15.2. Merits and deficiencies of Hennigian cladification 
 15.2.1. Phylogeny 
 15.2.2. Classification 
 16. Resolution of the conflict
 16.1. Stating the conflict 
 16.2. Which system is superior?
 16.3. Termination of the conflict 
 17. Glossary
 18. Literature Abstract The enormous variety of things in nature must be ordered before it can be studied and understood. Unfortunately in spite of their great importance, the methods of ordering have been greatly neglected by the philosophers. In this article, we distinguish six systems of ordering. Classification, in which similar entities are grouped in classes (taxa), is one such ordering system, but not all ordering systems are classifications. The Hennigian system of cladification consists of the ordering of branches of the phylogenetic tree, strictly on the basis of a single criterion, the branching points of the phylogeny (holophyly) (Hennigian phylogeny). It is not a system of classification, as it does not lead to classes of entities possessing similar phenotypic attributes. A Darwinian classification, by using two criteria, similarity and common descent, leads to the recognition of classes (taxa) of similar entities consistent with common descent (monophyly) (Haeckelian phylogeny).