3.317 To stipulate values for a propositional variable is to give the
propositions whose common characteristic the variable is. The stipulation
is a description of those propositions. The stipulation will therefore be
concerned only with symbols, not with their meaning. And the only thing
essential to the stipulation is that it is merely a description of symbols
and states nothing about what is signified. How the description of the
propositions is produced is not essential.


3.318 Like Frege and Russell I construe a proposition as a function of the
expressions contained in it.


3.32 A sign is what can be perceived of a symbol.


3.321 So one and the same sign (written or spoken, etc.) can be common to
two different symbols--in which case they will signify in different ways.


3.322 Our use of the same sign to signify two different objects can never
indicate a common characteristic of the two, if we use it with two
different modes of signification. For the sign, of course, is arbitrary. So
we could choose two different signs instead, and then what would be left in
common on the signifying side?


3.323 In everyday language it very frequently happens that the same word