What is the role of slang in society adopting a systemized language base? how and why does some slang make it into the dictionary? In the novel 1984?

Newspeak was not about creating slang more than about the systematic destruction of the English language. This destruction or rather de-construction of words turned into what can be considered a type of slang. It was, however, a slang meant to limit expression rather than further it. Slang made it into the Newspeak dictionary only if it served the primary function of limiting personal expression and self-identity. The more that morphed words robbed a person of individual identity, the more widely used they became. Positives and negatives were mixed together , "bad" became "ungood." The ultimate point was to create an emotionless, sexless and communal identity based on Party ideology.