Technical Artifacts, Engineering Practice, and Emergence 285
nature of the links or dependencies among real-world items [the emergent features and
the features of the emergence base]” (Van Gulick 2001: 16). According to Van Gulick,
epistemic emergence relations are therefore “in a sense subjective.” They are subjective
in the sense that whether a property is emergent or not depends on a knowing subject or
the knowledge base of a cognitive practice. We consider also limiting cases in which issues
of epistemic emergence become decoupled from a knowing subject or a knowledge
base.
Many different epistemic readings of the the notions “novel,” “qualitatively different,”
and “reduced” may be considered, each leading to its own criteria for deciding whether a
feature is epistemically emergent.^19 Here we pick out two such criteria, namely nonpredict-
ability and nonexplainability. The reason for these choices is that prediction and explana-
tion are two cognitive “tools,” which are of paramount importance for the engineering
control paradigm.
Both criteria come in different forms (see fi gure 16.1). The fi rst form of nonpredict-
ability, to be called “theoretical” (or a componentibus) nonpredictability, implies that a
systemic feature of a technical system cannot be predicted on the basis of knowledge about
its components. The second form is “inductive” nonpredictability, which implies that a
systemic feature cannot be predicted using generalizations based on observed cases. For
the moment, inductive nonpredictability does not concern us, since we are interested in
predictability on the basis of knowledge of elements from the emergence base. Theoretical
nonpredictability comes in a strong and a weak form; in its strong form, a feature is in
principle not predictable even on the basis of complete knowledge about the behavior of
its components.^20 This kind of nonpredictability has been a topic of intensive research in
chaos theory (see, e.g., Bertuglia and Vaio 2005). In the weak sense, theoretical nonpre-
dictability is conditional on the existing state of knowledge (about the emergent features
themselves, the features of the emergence base, and the laws of nature). Nonexplainability
also comes in a strong and a weak sense: a feature is strongly nonexplainable when it
StrongNonpredictable WeakStrongNonexplainable
WeakTheoreticalInductiveFigure 16.1
Various notions of “nonpredictable” and “nonexplainable.”