Catalysis and Scaffolding in Semiosis
We analyze the concepts of semiotic catalysis (or semiocatalysis) and semiotic scaffolding (or semioscaffolding) in the framework of general semiotics. Semiotic catalysis (as different from chemical catalysis) concerns the qualitative aspects of catalysis
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Catalysis and Scaffolding in Semiosis Kalevi Kull
The aim of this chapter is to find the place for the concepts of semiotic catalysis and semiotic scaffolding in the conceptual system of general semiotics. Following Kenneth Cabell (2012), we find it reasonable to distinguish between four partly overlapping—as if Borgesian—types of catalysis: chemical catalysis (if the catalyst reduces the activation energy of the chemical reaction), enzymatic catalysis (if the catalyst is enzyme), autocatalysis (if the process is intensifying itself), and semiotic catalysis (if the catalyst is a sign process). We start from the question on the semiotic aspects, as these appear in enzymatic catalysis close to the lower semiotic threshold.
Enzymes with Semiotic Features: Where Chemistry Turns into Something Else Enzymes seem to be, at least to those molecular biologists and biophysicists who are building their models, just molecules, complex molecules that behave like other molecules do, only being more complex. However, the features that they have may make them objects that need to be considered as something quite principally different. Medical chemistry, already since Paracelsus in the sixteenth century, has attempted to identify the characteristics called signaturen, e.g., in plants, which can be related to the power of healing (for instance, Leonhardt Thurneysser in Berlin, and Giambattista della Porta in Naples) (Jahn 1998, p. 214). In 1850s, Louis Pasteur argued that fermentation represents the sign or signature of life (Morange 2000, p. 11). Nowadays, the biological ferments are called enzymes. The term ‘enzyme’ was coined in 1878 by Wilhelm Kühne, a biologist of Heidelberg, editor-in-chief of “Zeitschrift für Biologie,” a teacher and colleague of Jakob von Uexküll. According to Kühne, an enzyme is “something that occurs that exerts K. Kull () Department of Semiotics, University of Tartu, Jakobi St. 2, 51014 Tartu, Estonia e-mail: [email protected] K. R. Cabell, J. Valsiner (eds.), The Catalyzing Mind, Annals of Theoretical Psychology 11, DOI 10.1007/978-1-4614-8821-7_6, © Springer Science+Business Media New York 2014
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this or that activity, which is considered to belong to the class called fermentative.” Contemporary definitions of the term are often no less cautious: “enzymes are the biological catalysts that specifically catalyze chemical reactions in living cells” (Kendrew and Lawrence 1994, p. 325). What is the reason to be cautious? In what sense are the enzymes not just chemical molecules like any other? In case of inorganic and simple organic molecules, the structure of the molecule determines the reactions that the molecule can enter. Accordingly, the nomenclature of these molecules corresponds to their structure. If we know the structure, we can identify the name, and all the features are thus connectable with the particular structure. In case of enzymes, the situation is radically different. The reactions that can be catalyzed by an enzyme molecule are not determined by its primary or secondar
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