[﹖
G.E. Moore (used in
Tractatus, p.
158–9, but with W–F instead of
a–b)]
It seems at first sight as if the
a–b notation must
be wrong, because it seems to treat true & false as on exactly
the same level. It must be possible to see from the
symbols themselves that there is some essential difference
between the poles, if the notation is to be right; & it seems
as if in fact this was impossible.
[True] How asymmetry is introduced is by
giving a description of a particular form of symbol which we call a
‘tautology’
. The description of the a–b
symbol alone is symmetrical with respect to a & b; but
this description & the
fact that what satisfies
the description of
the || a tautology
is a tautology is asymmetrical with regard to
them. (To say that a description was symmetrical with
regard to 2 symbols, would mean that
|| we could substitute one for the
other, & yet the description remain the same,
i.e. mean the same.)