>>105571156
OOP makes the language more complex which makes specifying it in a formal language harder and if you don't have a formal spec of your language then you can't formally prove anything about the programs in that language.
where is the python formal spec? where is the c++ formal spec? where is the java formal spec? of course they don't exist. to be fair I don't think Haskell is formalized either and it's also a very complex language. but C is formalized, standard ML is formalized, I'm sure some variant of Scheme is. all relatively simple languages compared to the OOP behemoths.