How does the author use foreshadowing in Portnoy's Complaint?

In every section of this complicated, multi-layered and richly textured novel, there are foreshadowings, revelations of character, hints of meaning, glimpses of relationship between past and present, and vividly defined slashes of powerful feeling. This chapter is no exception. After the undeniably compelling opening lines, the narrative introduces the central relationships (between Alex and his parents) and simultaneously introduces the central conflict (between Alex's needs and beliefs about himself and his parents'). There are also glimpses of explanation here of why the narrator became who he did in his business life (an advocate for the rights and dignity of the kind of people his mother so obviously despised), and of the novel's repeated equating of bodily function with spiritual condition. In this case, his father's physical constipation equates with his emotional and spiritual constipation—as the narrator himself puts it later, in both wayshis father is full of shit. (Chapter One)