Witti-Buch2 2001.qxd - Austrian Ludwig Wittgenstein Society

Logic vs. Information -
Two Approaches To Language
Jan Werszowiec Plazowski, Marek Suwara
Abstract
Examining language as a means of communication and expression of knowledge led to
two different approaches: one based on set theory - in which the language is reduced to
its formal structure, the other based on system theory - in which language is seen as
carrying information.
The thesis of the present paper is that a sentence, before it gets accepted as a part
of our knowledge, gets “filtered” through two different selection criteria. One, which
extracts the information available from a given sentence, is contextual. The other is
purely logical and “filters” the true sentences according to well-known criteria. While the
latter is pretty well described in literature, the former needs much wider study.
An example of the mentioned double-fold filtering can be a denial of liar’s paradox
on the logic-information ground. Although seen as a paradox, by large number of
logicians, the liar’s problem has no influence on our cognition or use of natural language
for cognitive purposes. The reason is simple. As we are going to show, in case of liar
paradox we analyse rather the reliability of the source of information than the lair’s
statement itself.
1. Introduction - logic and formalisation
Language as a foundation of our expression of knowledge has been a subject of many
studies. The present analytical approach resulted from some premises made on the
nature of a language - premises read from linguistic studies, and a programme of
formalisation, which for its founder, Leibniz, was supposed to purify the question of truth
quest in philosophy.
From linguistics were taken:
- thesis of the medium independence - linguistic objects get therefore
mathematical status (1)
- thesis of syntactical efficiency - properly build sentence is a sensible one (2)
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