256 Roberts
the supernatural in discussing natural phenomena. What later came to be
called “methodological naturalism” emerged as the reigning norm within
the Anglo American scientifi c community.^5
The elimination of God- talk from scientifi c discourse constitutes a
defi ning feature of modern science. In view of the important role that
theological categories had played within both natural philosophy and
natural history, it is not coincidental that at the same time students of
nature were attempting to detach themselves from such categories, they
were also beginning to employ new terms in describing their vocation.
The changes that occurred were neither abrupt nor universal; as late as
1830 John Herschel entitled his ambitious treatise on scientifi c methodol-
ogy A Preliminary Discourse on the Study of Natural Philosophy. Still, by the
time that Herschel published that treatise, the term “natural science” was
rapidly replacing “natural philosophy,” and by the end of the century the
label “scientist,” coined in the 1830s, was being widely used.^6THE EMERGENCE OF THE TROPE
During the late nineteenth century the term “science” underwent a sig-
nifi cant constriction. Although some thinkers continued to employ the
venerable defi nition of science as systematized knowledge, most began to
restrict their use of the word to the empirical investigation of natural (and
sometimes social) phenomena. In 1874 the conservative Princeton theo-
logian Charles Hodge, who three years earlier had described theology as a
science on the grounds that it took on the task of arranging biblical data
systematically, complained that the term “science” was “becoming more
and more restricted to the knowledge of a particular class of facts, and of
their relations, namely the facts of nature or of the external world.” Two
years later the liberal Protestant clergyman James Thompson Bixby simi-
larly observed that a “great revolution in thought” had occurred; whereas
“science” had once referred to “systematized knowledge of any kind,”
it now referred simply to “physical knowledge.” As a result, he opined,
the use of terms such as “the science of religion” or “the science of God”
now seemed “to involve a fi gurative extension of the word beyond its
proper sphere.”^7
By the second half of the nineteenth century, a wide variety of An-
glo American intellectuals had concluded that science and theology had
become distinctly different enterprises. Recognition of this fact underlay
the Baptist clergyman Samson Talbot’s acknowledgement of 1872 that
“mere physical science... begins and ends with nature.” Even Samuel