Well, one might say that the language does have the function of a tool but this is not the whole story. Language could become an object of language in its function as a tool and in cases like this the language is not a tool but an object of (linguistic) investigation. Further, while trying to cope with all sorts of issues, the language constantly evolves, as we know, towards syntheticity, i.e. towards becoming simpler. And since the communicative function of the language is if not the main one at least one of the main ones we should remind ourselves that the language, even if tool, is a complex living entity of its own. At the end, we should also remember that there are things which are not linguistic, like the physical world, to give an example, and the language according to some appeared to cope with non-linguistic stuff in the first place.
… the answer is, in essence, that during this century of science’s greatest achievements, most physicists and philosophers have given up on the idea that the purpose of science is to discover how the world really is. Instead they want to regard it as a mere instrument for making predictions and achieving pragmatic goals.
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