Sir Peter Teazle is a character in Irish playwright Richard
Brinsley Sheridan’s School for Scandal. Mulligan
seems to imply that Stephen's mother lost her mind toward the
end of her illness: "She calls the doctor sir Peter Teazle and
picks buttercups off the quilt. Humour her till it's over."
But Joyce's mother did the same thing and there is no evidence
that dementia was involved.
Sheridan was a Dublin-born playwright who moved to London
with his family at age 7. He lived there for the rest of his
life and was buried in the Poets' Corner in Westminster
Abbey. In his celebrated comedy of manners, The
School for Scandal (1777), Sir Peter Teazle is unhappily
married to a much younger woman and tormented by the
scandal-mongers' reports of her amatory adventures. He
suspects the spendthrift Charles Surface of being his wife's
lover and seeks help from his seemingly responsible brother
Joseph Surface. But in fact Joseph is the one carrying on with
Lady Teazle and Charles' heart is good. Sir Peter is a decent
person, but his stiff formality and his inflexibility of
judgment lead him to misjudge surfaces.
Richard Ellmann suggests that when May Dedalus referred to
“the dapper doctor” attending her as Sir Peter Teazle, it was
not a sign that she was losing her grip on reality. Rather,
she was attempting “to be lighthearted” (135). Given the
smugly inflexible way in which many doctors form and maintain
their opinions, this seems a reasonable inference. If Stephen
has told his companion such a story, then Mulligan has jumped
to a comically degrading conclusion, showing a cavalier
disinterest in the person that Stephen's mother actually was.
His fancy of picking flowers off the bedspread is consistent
with this spirit of cruel mockery.