"Had he been laughed at, to adopt the Freudian theory, in his cradle by a pretty girl?"
Sigmund Freud (1922)
Public DomainSigmund Freud (1922) - Credit: Max Halberstadt (1882-1940)

Here the narrator indicates that knowledge about the theories of Sigmund Freud, the Austrian physician who founded psychoanalysis, was part of the cultural climate of the period.

Specifically, this is a reference to Freud's belief that very early experiences in the life of an infant are highly influential in his/her emotional development.

Freud's work was available in English from 1913 onwards when his Die Traumdeutung (1899) was published in English translation under the title The Interpretation of Dreams. Interestingly, from 1924 onwards, the Hogarth Press, which was owned by Virginia Woolf and her husband Leonard Woolf, became the authorised publishers of the work of Sigmund Freud in England.

Hogarth Press commemorative plaque, Richmond, Surrey
GNU Free Documentation LicenseHogarth Press commemorative plaque, Richmond, Surrey - Credit: taken by Mark Barker - original uploader:MaxHund at en.wikipedia, Wikimedia Commons