Chapman and Carnap's "Meaningless" systems

By Roger Bishop Jones

for the Carnap Corner

On Tuesday 16 Feb 2010 00:08, J. L. Speranza wrote:

> As Chapman notes, the agenda of regimenting FL vs. NL is already
> there in the Intro to this book (Cfr. Carnap's two lectures in
> London):
>
> "In the introduction to The Logical Syntax of Language", Chapman
> expands, "Carnap presents a typically LOGICAL POSITIVIST accont of
> the PHILOSOPHER's reason for taking language seriously."
>
> Seriously? This seems like the antonymy of seriousness to me, but I
> see her point.
>
> "A suitably rigorous language will provide the necessary tools for
> logical and SCIENTIFIC exposition. This language is to be a FORMAL
> SYSTEM, concerned with types and orders of symbols but paying no
> attention to MEANING."

Chapman is fantasizing about Carnap here I believe, though I have not
actually read "Logical Syntax".

I believe Carnap, as a formalist, is like Hilbert (probably was
influenced in this by Hilbert rather than Frege).
Hilbert was not a formalist who regarded formal languages as
meaningless.
His formalism consisted in requiring meaning to be expressed
purely through a formal axiomatisation (often called an implicit
definition).

Carnap systematised this idea in his Philosophy of Logical Syntax, in
which he syntacticised all the relevant semantic concepts.
He did not regard his formal languages as meaningless, he simply
advocated that the semantics be rendered through the rules which
defined the analytic sentences.

RBJ