disciplines make eclectic use of any approach that turns out to be fruitfully applicable
while the conceptual gap may persist.
Lewens puts forward the view that applying evolutionary accounts when explaining
technological innovation is all too obvious to be denied but that the way in which evolu-
tionary theory is applied to the cultural fi eld is usually not the most fruitful way. What is
generally acknowledged is the wide range of factors responsible for variation and selection
in the fi eld of engineering. However, Lewens delineates another important aspect of evo-
lutionary approaches that requires closer consideration since it is acknowledged to be one
of Darwin’s important ideas but is not yet fully accepted as a basis for the explaining of
technical innovation. It is the notion of population thinking as an alternative to typological
thinking. He shows that population thinking in the version put forward by Richerson and
Boyd (2005) is a most promising approach that may help to understand creative intentional
processes in evolutionary terms. Considering theories of cultural change that ascribe fi tness
values to memes in the way that evolutionary biologists ascribe these values to organisms,
Lewens demonstrates that even with these theories, which are based on typology and are
not in line with Richerson and Boyd’s approach, the inclusion of population level factors
is indispensable in explaining evolutionary processes.
Krohs takes the example of the evolution of modular systems and compares biological
accounts of the evolution of modules with what is known about the evolution of modular
systems in engineering. A main line of argument used in attempts to explain the evolution
of biological modularity is to explain modularization as a process of adaptation. Krohs
argues that these explanations are incomplete. Though they explain the evolution of
modules, most of these explanations cannot account for the fact that modularity is also
restricted, that the borders of modules are fuzzy, and that a high degree of nonmodularity
is present in many organisms. He proposes amending the arguments by considering not
only the benefi ts but also the various kinds of costs, known from technological modularity,
that modularity also entails for an organism. He fi nally discusses the problem of mapping
functions on a modular structure, given that the structural and functional decomposition
of biochemical and gene regulatory networks do not usually yield coinciding modular
boundaries, and that almost any particular function within a molecular network is to be
regarded not as being ascribable to a single component or module, but rather as being
distributed over a large part of the whole network.
Kroes deals with the topic of emergent properties of technical systems. Emergence in
the epistemic sense is the occurrence of unpredictable, novel systemic properties. He asks
how this unpredictability affects the control paradigm in engineering. According to this
paradigm, engineering practice aims at complete control of the behavior of a system by
controlling the behavior of its constituent parts. It is precisely this that seems to be threat-
ened by emergent behavior. He maintains that three issues related to the occurrence of
emergent features in technical systems are particularly important in engineering practice:
- emergent causal powers, 2) the tension between emergent features and functional
224 Part V