Language and thought define reality. The party is creating a new language, it is called newspeak. Newspeak is similar to English with a large amount of words left out. For instance if you took a word like "good" and it's opposite "bad", in newspeak they would not use the word bad they would simply say "ungood". In this way they destroy words and with that the ability to express ones self. The idea behind this is, if there is no word to express an idea they can stop you from saying or thinking anything they don't want you to. When newspeak is finished thought crime will be impossible. The thought of not having a language that you can express yourself in even in thought is a frightening one.