Criteria for a Good Theory in Physical Science

A now famous instance of this sort appears
in the publication (1939) by Otto Hahn and
Fritz Strassmann, who originally (but unfairly)
received all the credit for the experimental discovery
of nuclear fission. At that time it was
still axiomatic in the thinking of many scientists
that nonradioactive atomic nuclei are stable,
that bombardment with small particles (e.g.,
neutrons) may at best dislodge an alpha particle
or two. But these two men, after firing neutrons
into pure uranium, were left with material that
by chemical test was proved to contain barium
(Ba) and other elements whose atoms are about
half as large as uranium atoms-”evidently” as
we would say now, the result of splitting uranium
atoms. But in an almost agonized expression of
the labor pains attending the birth of all great
recognitions, Hahn and Strassmann could not
dare to accept publicly the evidence of their own
chemical experiments, and so they wrote:
As ‘nuclear chemists,’ in many ways closely
associated with physics, we cannot yet bring
ourselves to make this leap in contradiction to
all previous lessons of nuclear physics. Perhaps,
after all, our results have been rendered deceptive
by some chain of strange accidents.
(“Concerning the existence … ,”
Naturwissenschaften)

A note on the human dimension behind scientific
publications: It was their colleague Lise
Meitner, forced to leave Germany by Nazi
assaults on Jews, who first recognized that the
Hahn-Strassman observations implied nuclear
fission, and with her nephew Otto Frisch worked
out the first rough theory of the process. Yet
Meitner was denied a share of the Nobel Prize
for the discovery, and she was only much later
given some recognition for it.