On the confusion of illustrations called cladistics

The science of large-scale change in biodiversity over eons of time, called phylogenetics and dealing with what is traditionally called “evolution”, contains a for science particular problem. The fact that the fundamental illustration of evolution, ie, a dichotomously branching graph describing “the origin of species”, is the only accessible visualization, and thus “observation”, of the process means that the illustration can easily be confused with the process itself. Such confusion does, however, contain consistency problems that are independent of this particular application, but are generic to illustrations of dichotomously branching processes.

The fundamental problem with this potential confusion resides in that such process can be described with two different kinds of graphs: stem-based and node-based (as discussed by Jeremy Martin et al.), neatly illustrated by Willi Hennig (1966, Fig. 14, p. 59), stem-based to the left and node-based to the right. These two kinds of illustrations are thus different illustrations of one and the same phylogeny. 

This possibility to illustrate one and the same process with two kinds of illustrations make confusion of the illustration (ie, a dichotomously branching graph in general) with the process itself inconsistent by confusing the two kinds of graphs. Confusion of a dichotomously branching graph with a dichotomously branching process is thus inconsistentent by confusing the two possible illustrations of the process with the process. 

This possibility to confuse two kinds of illustrations or not is actually a possibility to choose between subjectivity and objectivity, since confusing them is consistent with the approach resting on the axiom that categories (ie, subjects) are real, in biological systematics called “cladistics”, whereas not confusing them is consistent with the approach resting on the axiom that objects are real, in biological systematics called “evolutionary taxonomy”. The possibility to confuse these two kinds of graphs thus offers a possibility to choose between subjectivity and objectivity.

Although this possibility can’t distinguish the two incompatible approaches concerning their consistency, the fact that subjectivity confuses the two kinds of graphs means that it is consistently inconsistent. Both approaches are thus consistent, but only subjectivity is consistently inconsistent.

The science of phylogenetics thus offers a possibility to choose between subjectivity and objectivity, whereof subjectivity is consistently inconsistent whereas objectivity is consistent. Hence we must be careful not to confuse illustration with reality in order to avoid being consistently inconsistent.

Another contribution to understanding of conceptualization http://menvall.wordpress.com/

Read more at Menvall’s Blog: change on different levels