According to George Bernard Shaw,language is the barrier and source of distinction between the social classes in society.He is of the opinion that the type of language spoken by a person indicates his origin and social class.He depicts his this view very clearly,emphatically and beautifully in the play 'Pygmalion'.
In the Act 1,when different people gather in the portico of st.Paul church to take shelter from rain,they speak in different dialects and different manners.Each person's social class and origin can be judged by the manner in which he speaks nd by the language which he uses in his speech without even looking to him.This is portrayed by Professor higgins accurate guess aboutr the locality of each person standing there.He is scholar of london dialects but even a layman can guess atleast the social class by merely listening to the speech of a person.This too is clealrly indicated in the play.Anyone can tell that Eliza doolittle belongs to the lowest stratum of the society by simply noticing her language and her manner of speaking.
In act 3,when Eliza doolittle comes to a small gathering at Mrs.higgins house,she is exquisetly dressed with a very charming appearnace but she gives away her real origin by the type of slang she uses in her speech and by subjects of her talk.
Then transformation of Eliza by professor Higgins into a fine lady proves the power of language in distinguishing between classes.By merely making Eliza learn a fine language,she is turned into a fine lady.This truely depicts tht difference between a lady and a flower girl is merely a differnce between the type pf sounds they make while speaking.
In the last act,we see Alfred doolittle dressed in very fine clothes like some bridegroom,but even then anyone can judge his real origin by his language and way of speaking.The fine and expensive clothes can conceal his identity as long as he keeps his mouth shut.The moment he opens his mouth,his true origin is revealed.
So in the play pygmalion,the whole story portrays the langauge as a barrier between social classes and language as an identity of a person.