What are Higgins' reasons for taking Liza to his mother at home in Shaw's play "Pygmalion"? This question is taken from Pygmalion Act 3.

Mrs.
Higgins, Henry's mother, is schooled in the social graces and just happens to be having some
guests, the Eynsford Hills, over for a visit.  Henry, elated at the progress Liza is making
under his tutelage, wants to take the opportunity to test her progress in a social
situation. ...