In
general: When such propositions are analysed, while the
words ‘thing’, ‘fact’
etc. will disappear, there will appear instead of them
a new symbol,
|| of the same form as the one of which we are
speaking; & hence it will be at once obvious that we
cannot get the one kind of
proposition from the other by
substitution.
In our language names are
not
things: we don't know what they are: all we
know is that they are of a different type from relations
etc. etc. … The type of a
symbol of
a relation is
partly fixed by
the type of
a symbol of
a thing, since a symbol of
the latter type must
occur in it.