13 Shannon entropy of a signal is the probability of a given signal being

13 shannon entropy of a signal is the probability of

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Shannon-entropy of a signal is the probability of a given signal being present in a given physical context. In short, the informational concept of entropy cannot be reduced to the physical one, since the former, when used about something, specifies something as standing in the foreground of attention (“the potential winners”), while countless other aspects of the physical situation are deemed irrelevant (say, the armchairs in the room, or the interaction between molecules). Different from Shannon-information is what Puddefoot calls shaping information , which is the form or pattern of existing things. Here the interest lies in morphology, the study of forms, or on specific characteristics. Shaping information may derive either from internal sources (such as a zygote) or from external constraints that cause something to have a definite pattern in relation to its environment. This shaping information is what Shannon-information is about when subsequently used to acquire knowledge about the environment. But notice that the shaping information is countless in the world surrounding us, depending on all kinds of boundaries that could fall under observational interest, as well as on the scale of investigation. For example, is the snail and its house one shape, or a compound of two? I therefore suggest to make a further distinction in the general category of “shaping information”. Shaping information seems to have two forms, either in form of the mere production of differences (as in quantum events), or in the form of larger-scale semi-stable or resilient structures in the classical domains of physics, chemistry, and biology. In the next section, I refer to these two forms of shaping information as “cutting-information” and “channeling information”. The third type of information is what we refer to in daily parlance: coming to know something of importance. In meaning information, information is not only about something, but is of interest for somebody in a given situation . An approaching military helicopter can either be a neutral fact of no importance, it can be a salient sign of a fatal combat, or it can be the long-awaited 14
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rescue. In meaning information, we are not only interested in the fact that there is this or that feature in our environment (to which we may refer), but we are interested in what it means to us . Information is here part of a process of communication, as pointed out by Bernd-Olaf Küppers (chapter 9, this volume). 8 As argued by both Deacon and Jesper Hoffmeyer (Chapters 8 and 10, this volume), the aspects of salience and aboutness may already be present at biological level. However, wherever we identify the entrance of meaning information (at basic cellular level, at brain level, or at the level of human communication) we cannot slide easily from one aspect of information to another. Novel informational features are emerging in the course of evolution. It seems to me, however, that the concept of shaping information is basic in relation to the two other forms of information . Counting
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