Complexity and information
Choice Reviews Online · 2000
\Complexity" is a catchword of certain extremely popular and rapidly developing interdisciplinary new sciences, often called accordingly the sciences of complexity 1 .It is often closely associated with another notably popular but ambiguous word, \information" information, in turn, may be justly called the central new concept in the whole 20th century science.Moreover, the notion of information is regularly coupled with a key concept of thermodynamics, viz.entropy.And like this was not enough, it is quite usual to add one more, at present extraordinarily popular notion, namely chaos, and wed it with the above-mentioned concepts. 2 It is my aim in this paper to critically analyse this conceptual mess from a logical and philosophical point of view, concentrating on the concepts of complexity and information, and the question concerning the true relation between them.I shall focus especially on the so-called algorithmic information theory, which has lately become extraordinarily popular, especially in theoretical computer science and in the above-mentioned new sciences of complexity indeed, today one can hardly open a popular science book without meeting this theory 3 .It is notable that this approach simply equates information content with complexity and it is furthermore regularly o ered as the preferable explication of the notions of entropy 4 and chaos 5 .This theory has also been a source of various rather fantastic philosophical speculations. 61 \Information" in ordinary language Before taking a closer look to the various technical approaches called { with better or worse justi cation { information theories, let us for a moment consider what one usually actually means by the word \information" in ordinary language.This is because I aim to evaluate how w ell various theories of information that have been put forward actually capture this pretheoretical notion, i.e. how apt explications of the informal concept of information they really are.