Writing in the same journal in which Mayr's proposal appeared a few weeks ago, Woese now attempts to rebut Mayr's ideas with an apparent singular vehemence, proposing that the issue is more profound than that of merely assessing the utility of a classification scheme. Woese's idea, apparently, is that the trichotomous classification scheme is discovered rather than constructed, which implies a significant problematic philosophical subtext that is not amplified in his paper. A biological classification is in effect an overarching evolutionary theory that guides our thinking and experimentation, and it must be structured to reflect evolutionary reality. The prokaryote- eukaryote dichotomy, which Mayr proposes to reinstitute, is a failed taxonomic theory that was never recognized as theory and therefore never tested in a timely fashion, with the consequence that it has adversely affected the development of biology, especially microbiology, in the latter half of this century. The scientifically perceived importance of a group of organisms must reflect the natural importance of the group.
Microbial diversity is far more than a listing of distinguishable microbial species.
We need to understand the quality of microbial diversity, for it is the diversity that defines the biosphere of this planet. Any comprehensive understanding of a biological entity, be it an organism or a molecule, necessarily has an evolutionary component. It concerns the nature of Biology itself. His is the biology of visual experience, of direct observation. The science of biology is very different from these two perspectives, and its future even more so.