Humbert recounts his more general relations to women during his college years.
He considered getting a degree in psychiatry but then switched to English literature, which he studied in Paris.
He begins publishing and finds a teaching job.
Humbert introduces and details the term "nymphet" (1.5.5); nymphets are girls between 9 and 14 and don't have to be good looking. To discern a nymphet is also a skill – you must yourself be, as he says, an "artist and a madman" (1.5.6).
There must be a gap of at least ten years between the man and his nymphet. Thus, by definition, Annabel is not one but his love for her fueled his love of nymphets.
Living in Europe, Humbert had relations with many women, all of whom are substitutes and many of whom are prostitutes; taboo prevents him from being with a girl of twelve, but he spends plenty of time staring at them in parks.
Humbert recounts many examples from literature and history in which poets and leaders loved much younger girls.
He "tried hard to be good" (1.5.19), spending many days sitting on a park bench ogling nymphets but restraining himself.