rvations
change at once when the investigator sets about gathering as much of the
material as he can secure, and changes constantly as he formulates
tentative hypotheses for the solution of the problem, which, moreover,
generally changes its form during the investigation. I am aware that
this change in the form of the data will be brushed aside by many as
belonging only to the attitude of mind of the investigator, while it is
assumed that the "facts" themselves, however selected and organized in
his observation and thought, remain identical in their nature
throughout. Indeed, the scientist himself carries with him in the whole
procedure the confidence that the fact-structure of reality is
unchanged, however varied are the forms of the observations which refer
to the same entities.[35]

The analysis of the fact-structure of reality shows in the first place
that the scientist undertakes to form such an hypothesis that all the
data of observation will find their place in the objective world, and in
the second place to bring them into such a structure that future
experience will lead to anticipated results. He does not undertake to
preserve facts in the form in which they existed in experience before
the problem arose nor to construct a world independent of experience or
that will not be subject itself to future reconstructions in experience.
He merely insists that future reconstructions will take into account
the old in re-adjusting it to the new. In such a process it is evident
that the change of the form in the data is not due to a subjective
attitude of the investigator which can be abstracted from the facts.
When Darwin, for instance, found that the marl dressings which farmers
spread over their soil did not sink through the soil by the force of
gravity as was supposed, but that the earthworm castings were thrown up
above these dressings at nearly the same rate at which they disappeared,
he did not correct a subjective attitude of mind. He created in
experience a humus which took the place of a former soil, and justified
itself by fitting it into the whole process of disintegration of the
earth's surface. It would be impossible to separate in the earlier
experiences certain facts and certain attitudes of mind entertained
by men with reference to these facts. Certain objects have replaced
other objects. It is only after the process of analysis, which arose
out of the conflicting observations, has broken up the old objec