Wittgensteinian exegesis is a graveyard.
A characteristic of a language is that it is a symbolic system with a method of assigning meaning to its symbols. So a private symbolic system does not satisfy these conditions, so it cannot assign meaning, so it is not a 'language'. I object to Assertion 2. I cannot see any justification for the narrowness of the conditions in 2'. A characteristic of a language is that it is a symbolic system with a method of assigning meaning to its symbols.