I'm not sure what you mean by "inciting moment," but I guess
the term refers to what "incites" the rest of the action, or what
"incites" Winston to break the rules of the party in the first
place. Following this definition, the very first inciting
moment would be when he experienced desire for the book in which he
writes his forbidden thoughts, for it is desire that the party
wants to eradicate above all else. The desire for the book is
a prelude to all of his other desires, including the desire to
hope, and especially the desire to love and be loved. Here is how
the narrator presents this moment:
seen it lying in the window of a frowsy little junk-shop in a
slummy quarter of the town . . . and had been stricken
immediately by an overwhelming desire to
possessit. Party members were supposed not to go into
ordinary shops . . . but the rule was not strictly kept . . .
. He had given a quick glance up and down the street and then had
slipped inside and bought the book for two dollars fifty. At the
time he was not conscious of wanting it for any particular purpose.
He had carried it guiltily home in his briefcase.
Even with nothing written in it, it was a compromising
the highlighted words call attention to the inciting nature, the
transgressive nature, of this moment of wanting, and then acting on
the want contrary to party rules.