Presented with Malte Ebach at UNSW

1. Natural classification
John Wilkins and Malte Ebach

2. • “All science is either physics or stamp collecting!”
• Two responses:
• 1. Actually other science is also like physics: Physics envy
• 2. Stamp collecting is valuable
• I want to discuss the history of these views and argue that we need natural
classification to make sense of that history and modern science
Rutherford's dictum

3. • Scientific ontology is derived from theory
• "Theory is not solely an economical representation of experimental laws; it is also a
classification of these laws" (Duhem 1914 23)
• "When the zoologist asserts that ... a classification is natural, he means that those ideal
connections correspond to real relations among the associated creatures brought
together and embodied in his abstractions" (25)
• Classification is held to be an intellectual operation on abstract ideas.
• Since theory is self-standing, the only ideas that matter are theoretical
• Similar views held by Kuhn, Lakatos and Popper
• Two schools:
• Evolutionary conventionalism
• Philosophical theory-derivation
The standard view of classification:

4. • Although Darwin was a standard systematist (Strickland Code), his ideas were
immediately thought to undercut taxa
• If species evolve, then they are not real
• We classify based on "evolutionary novelties"
• By the sesquicentenary of the Origin, the standard view was that classification
was a matter of convenience (Conventionalism)
• Colloquium in American Naturalist in 1908, Botanical Society of America
meeting
Darwin and the decline in systematics

5. • From c1900, philosophy moves away from evolution and natural classification
• John Dewey reduces classification to librarianship
• Russell and Moore reject evolution philosophically
• Classification becomes a matter of our best theory and convenience
• F. P. Ramsey suggests we formalise theories as logical sentences
• Hence, an object exists so long as it is the kind of thing that can be represented
as a variable in that logical (or Ramsey) sentence:
• Quine's slogan: "To be is to be the value of a variable" ("On What There Is",
1948)
• This is an essentialism: the ontology of a theory is the definitional essences deduced
from the variables of the theory
Philosophy and classification

6. • Obviously, biological sciences classified from the beginning
• We still recognise, e.g., species defined in the 16thC by Bauhin, Gesner and
others, well before any theory
• While Linnaeus's scheme was not meant to be "natural", natural
classification was the goal in the late 18thC to early 19thC
• Adanson
• A. L. de Jussieu
• W. S. Macleay
• Whewell
• Not just in biology, though...
What is wrong with this?

7. • Mineralogy (Mohs, Linnaeus)
• Chemistry – elements, atomic weight, spectrum analysis
• Leading to an empirical periodic table
• Medicine - classifying disease
• Psychology
• DSM - etiology versus phenomenology
• Earth sciences
• Rock types
• Soil types
• Ecology
• Ecotypes
• Biogeographical regions (Wallace)
Classification in the other sciences

8. • The problem of theory-dependence of observation
• Can naive observation happen?
• Nobody starts by knowing nothing; no tabula rasa
• Prior knowledge:
• Folk science and taxonomy
• Linguistic categories
• Psychological dispositions
• Berlin's Five level theory
• Evolutionary psychology
• Kantian synthetic a prioria are evolutionary a posterioria – Lorenz
• Is any of this theory?
Natural classification and observation

9. Theory-relativity
• A theory is relative to a domain of investigation
• If the domain lacks a theory, it does not mean we have no theory
• For example, did Galileo's observation of the moons of Jupiter need the
theory of optics? (What about children that could see them with the naked
eye?)
• So is "naive" observation possible?
• Platnick and the spinneret
• The five year old test

10. • Conceptual
• Passive (classification) to active (theoretical explanation)
• Empirical
• Passive (naive observation) to active (experimental intervention)
• Rather than a set sequence or algorithm of discovery (“scientific method”), this
sets up a field of possible steps and activities for a researcher, research group,
program or discipline
• Individually, each active researcher, etc., will strive to balance promising
activities against costs and likelihoods of success
• In a field that has elaborate successful theories, naive classification will be
deprecated
Science as a field of opportunities

11. B: Baconian induction
P: Popperian GTR

12. Exp Cla Obs The
Exp Revision and
correction
3. Experiment can
suggest
classification
category
11. Experiment can
restrict or guide
“naive”
observations
2. Experiment can
restrict theoretical
range, or
disconfirm theory
Cla 4. Classification can
suggest things to
measure and expect
Revision and
correction
5. Classification can
guide the evidence
sought
10. Classification
can restrict or
guides the ontology
of a theory and the
explanatory
categories used
Obs 12. Naive
observation can
influence the data
used in experiment
6. Classification can
be based on naive
observations made
pretheoretically
Revision and
correction
7. Theoretical
predictions can fail
to be borne out in
observation
The 1. Theory can
specify legitimate
experimental
protocols and
9. Theoretical
variables can
become
classification
8. Observation can
depend upon the
ontology and
methodology of a
Revision and
correction

14. Some principles
• Classification sets up the explicandum that theory explains
• Theory can change a natural classification via iterative refinement (reciprocal
illumination)
• Observation can be domain-theory-free and therefore “naive”
• Everyone has some knowledge prior to investigation
• Some observation is theory-dependent
• There is no set sequence for a domain’s development: it depends upon the
broader discipline and how it is located within science generally

15. Science is a Dance Floor
There’s room for everyone

16. “OK, let’s slowly lower in the grant money.”