There are several themes in Pygmalion:
appearance vs. reality
phonetics and language education
the marginalization of women
the inadequacy of myth
The main theme, and one to which the others relate, is that of appearances versus reality. This theme of appearances is developed primarily through the characterization of Eliza Doolittle, but the others also come into play. For instance, as Professor Higgins works on his experiment with the flower girl from Lisson Grove, he instructs Eliza in elocution, and she learns how to speak as he does and to conduct herself as a lady [theme of education]. Then, with the proper clothes and expressions, Higgins plans to introduce her to society and observe whether anyone notices that she gives only the appearance of a lady of refinement and breeding [appearance vs. reality]. When Eliza attends a parlor party, Higgins's experiment is a success, even when Eliza unknowingly speaks of her aunt's death and her father's drinking because she speaks with such finesse [language education and appearances vs. reality] that Freddy, who gave her no audience in the beginning as she was but a flower girl, is now fascinated, believing that she is using the latest "small talk." However, before she departs, in the most famous line of the play blurts out, "Not bloody likely." This expletive shocks her listeners into reality.
Eliza's father also acquires a new appearance: that of a higher economic status since a wealthy American has left Mr. Doolittle enough money that the dustman can become a man of the middle class. [socio-economic transformation] However, he has not acquired the language skills that his daughter has, so that the reality of his beginnings is yet apparent. Still, he moves into a better class as he marries Eliza's mother.
In the Act IV of Shaw's play, there is an examination of the position of women in the Victorian society. Certainly, Eliza has been marginalized as she has been treated as a mere experiment and not a person with feelings. For, after Higgins returns home and Higgins congratulates him on winning his bet. When Higgins asks Eliza to find his slippers, she hurls them at him.
HIGGINS. What on earth--...Anything wrong?
ELIZA. [breathless] Nothing wrong--with you. I've won your bet for you, havn't [sic] ....I don't matter, I suppose.
HIGGINS. You won my bet! You! Presumptuous insect! I won it. What did you throw those slippers at me for?
ELIZA. ....I'd like to kill you, you selfish brute....You thank God it's all over, and that now you can throw me back again there, do you?....
HIGGINS. Ah! would you?....How dare you shew [sic]your temper to me?
ELIZA. ....Whats [sic] to become of me? Whats [sic] to become of me?
HIGGINS. How the devil do I know....What does it matter what becomes of you?
Further in this act, Higgins is cruel and uncaring, as well. In the final act, Act V, Eliza informs Higgins that she is leaving him to marry Freddy. Higgins scoffs at this. But, in the Epilogue, Shaw narrates that Eliza does, indeed, marry Freddy.
These confrontations between Eliza and Higgins illustrate not only the theme of the marginalization of women, but they also depict the inadequacy of myth. Like the story of Pygmalion, Higgins forms a beautiful woman, but because his is real flesh and blood, conflicts occur and perfection is not reached as there are problems that must be addressed, such as what is Eliza to do with the rest of her life after the bet is won.