No subject

[Juliette Kennedy]

Many thanks to Parsons, Sieg, Detlefsen and Joergensen for their very
informative answers and references regarding Hilbert's consistency
results.

Also I wonder if anyone would comment on the following passage from a
letter written by Frege to Husserl in 1906, on logical usage vs. existence
claims:

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"I have further doubts concerning the following. You write, "The form
containing "all" is normally so understood that the existence of objects
falling under the subject and predicate concepts is part of what is meant
and is presupposed ans having been admitted." It seems to me that you can
only give this the sense you want it to have if you strike out the words
"part of what is meant." ...Now I use the expressions containing "all" in
such a way that existence is neither part of what I mean nor something I
presuppose as having been admitted. Linguistic usage cannot be absolutely
decisive here., since we need not be concerned with what linguistic usage
is. Instead, we can lay down our linguistic usage in logic according to
our logical needs. The reason for the usage I have laid down is
simplicity. If a form of expression, like the one containing "all" is to
be used as a fundamental form in logical considerations, it is not
feasible to use it so as to express two distinguishable thoughts at the
same time, unless the proposition consists of two propositions combined by
"and". For one must always strive to go back to the elements, to the
simple. It must be possible to express the main thought without incidental
thougts. This is why I do not want the incidental thought of existence to
be part of what I mean when I use the expression containing "all".

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J.Kennedy
Helsinki