successful discovery-making equipment; these persons are in a position to refine
or modify the equipment to extend past lines of discovery-making. This applies
both to the accretion of small discoveries within a successful paradigm, which
generally takes place by small modifications or extensions of the application
of existing technique, and to major new lines of discovery, which typically arise
by the cross-breeding of lines of equipment or by the invention of radically
new research technology: the development of the electrical battery and its
combination with the equipment of chemical experiment, and thence with the
equipment of astronomy, and so onward.^8 There is no apparent limit to this
process in time; the combinatorial cross-breeding of research equipment gene-
alogies will apparently continue to generate phenomena for scientific discov-
eries as long as social networks exist to promote the equipment genealogies.
The lineages of research equipment are real, in the sense in which the world
of human-sized objects in time and space is real. They are lineages of material
things. The interpretation is sometimes made that scientific experiments are
embodied theories, that research equipment has a primarily mental reality. This
seriously overstates the case. The genealogy of equipment is carried along by
a network of scientific intellectuals who cultivate and cross-breed their tech-
nological crops in order to produce empirical results which can be grafted onto
an ongoing lineage of intellectual arguments. This is not to say that scientists
always experiment in the light of theories which give a supportable interpre-
tation of what their equipment is doing. Tinkering with the equipment, cross-
breeding it, or initially inventing it may be done with very little sense of the
theoretical issues that later develop out of it and provide a retrospective
theoretical interpretation of what the equipment is doing. Whether scientific
intellectuals have a clear and defensible theoretical conception of their equip-
ment or not, they engage in practical bodily action whenever they use equip-
ment. The network of scientists acts in the banal material time-space world,
and the theoretical entities which they discuss and pass along as the contents
of their science are grounded in this human-sized world of human bodies and
research equipment.
What then is the reality of the theoretical entities of science? As invisible
structures or substances they are prey to all the philosophical troubles which
arise whenever one attempts to step out of in medias res and into a realm of
perfect precision and enduring substantiality. Nevertheless, this does not make
them necessarily illusory or unreal. Theoretical constructs can acquire an
obdurate quality like that of the world of banal reality because they are linked
with it in at least two ways. They are a real focus of attention and, over time,
of consensus within a real network of scientists. This social consensus is of a
distinctive kind, oriented toward a lineage of discoveries about obdurate real-
ity, because scientific entities are also grounded in the material genealogies of
Epilogue: Sociological Realism^ •^871