Experimental Discovery, Data Models, and Mechanisms in Biology: An Example from Mendel’s Work - Mechanism and Causality in Biology and Economics - page 102

(although they respect him as one of the founders of experimental embryology)?
Historians have not given us a reasonable account.
In his discussion of “anomaly and the emergence of scientific discoveries,”
Thomas Kuhn ( 1970 , p. 62) specified three characteristics appearing in the process
of scientific discoveries: the previous awareness of anomaly, the emergence of both
observational and conceptual recognition, and the consequent change of paradigms.
Kuhn claimed that these are characteristics of all discoveries, from which new sorts
of phenomena emerge. One may well read the three characteristics as Kuhnian
conditions defining scientific discovery. The first condition would be satisfied when
an experimental result directed by a paradigm conflicts with the paradigmatic
theory and the result is treated as an anomaly by scientists in the normal period;
the second, when the anomaly is recognized as significant in both observation and
concept; and the third, when a new theory that is able to solve the anomaly is
generated.
One may invoke the three conditions to interpret why historians have such a
different assessment of the two cases above. Griffith's case satisfies these
conditions, because a new theory of hereditary material that could explain the
transformation was proposed by Avery and his team 4 ; Driesch's case does not
satisfy these conditions, because Driesch indulged in the old vitalistic paradigm.
The problem is that Griffith himself did not explain his experimental result,
although he did not commit to any “old” theory. If a new theory that is able to
solve anomalies proposed by other scientists can give the experimenter Griffith
credit for his “discovery,” then the later theory about conditional specification of
development should also entitle Driesch to be credited as a discoverer. 5 We should
regard Driesch as the discoverer of conditional specification in accordance with
Kuhnian definition of discovery, although a “correct” explanation of this phenome-
non came much later.
In appealing to Kuhn's view of scientific discovery, however, one should not
forget his doctrine of the theory-ladenness of observation. Based on this doctrine,
scientists' experimental observations presuppose their precedent paradigmatic
beliefs. Thus, Griffith did not observe and interpret the transformation pheno-
menon, nor Driesch the phenomenon of conditional specification, because they
could not correctly interpret their experimental results in accordance with their
paradigms. Thus, neither would be entitled to be called a discoverer. Here we see an
inconsistency in the Kuhnian view of discovery. According to the conditions of

4

Judson ( 1996 , p. 18) described the community's response to Griffith's experiment: “It raised
clouds of speculative and spurious explanations ... Avery at first found it impossible to credit
Griffith's paper. The findings seemed to overthrow his own fundamental demonstration of the
fixity of immunological types. But bacterial transformation was confirmed that same year in Berlin
and in 1929 was repeated at the Rockefeller Institute.” The description seems to accord with the
three characteristics of scientific discoveries specified by Kuhn.
5 In fact, Scott Gilbert, the author of a textbook of developmental biology, claimed that Driesch
“provided the first experimentally observable evidence of conditional specification” (Gilbert 2010 ,
p. 114). The current theory of developmental biology states that “conditional specification is the
ability of cells to achieve their respective fates by interactions with other cells” (Gilbert 2010 ,p.112).