Ornithology, Evolution, and Philosophy 123

Philosophy of Biology 363
“The replacement of typological thinking by population thinking is perhaps the
greatest conceptual revolution that has taken place in biology” (1963b: 5). Mayr’s
conceptualization of population thinking is a, perhaps the, major contribution to
the philosophy of biology. He mentioned population thinking for the first time in
print in his textbook, Methods and Principles of Systematic Zoology (1953a; see
above p. 321, also p. 312) and formally introduced this concept in his article on
“Darwin and the evolutionary theory in biology” (1959b).
During the 1950s, Mayr became acquainted with the literature of philosophy of
science and was disappointed. This was a philosophy of logic, mathematics, and
the physical sciences and had nothing to do with the concerns of biologists (1995j,
1997b: XI). When Snow (1959) spoke of two cultures, science and humanities,
physics was for him the exemplar for science. For some physicists “all biology
is a dirty science” because nice clean laws without exceptions do not exist in
large parts of biology. This reflects the nature of biological phenomena, but some
workers thought that biology could be reduced completely to physics.
The rise of a philosophy of biology began with the evolutionary synthesis as
a contributing factor, when teleological and typological (essentialistic) concepts
were eliminated from biology and continued especially during the 1960s with Mayr
being a driving force. His books and articles in this field were mostly written from
the point of view of evolutionary biology and provide a conceptual framework
of biology and the basis for a new philosophy of science that incorporates the
approaches of all sciences, including physics and biology. His publications in philosophy
of biology were written in a lucid graceful style accessible to all interested
biologists and knowledgeable persons. His main objectives were to help his readers
to “gain a better understanding of our place in the living-world, and of our
responsibility to the rest of nature” (1997b: XV).
“The New versus the Classical in Biology”
The above account documents the early origin of Mayr’s genuine interest in philosophical
aspects of biology, particularly of systematics and evolution during the
modern synthesis of the 1940s (“internal causation” of his interest). This interest
grew stronger during the 1950s after he had joined the staff of the MCZ at Harvard
University, when he dealt increasingly with general problems of evolutionary
biology at a time when molecular biology, the new glamor field, threatened to dry
up nearly all research funds available and classical organismic biology began to
lose ground. Mayr became spokesman of systematics and evolutionary biology in
the United States, especially after he had assumed the directorship of the MCZ in
1961. He criticized the generally unbalanced situation in American science such
as, for example, the replacement of seven of eight retiring professors of biology at
Harvard University by molecular biologists. Anyone in a more traditional area of
biology had considerable difficulties in attracting promising students, and whole
fields, especially of invertebrate zoology, became depleted of specialists. In view
of this situation he wrote an editorial on “The New versus the Classical in Biology”