The unnamed narrator of “Motherhood,” Sheila Heti’s earthy and philosophical and essential new novel, is a writer in her late 30s. She smokes; she’s divorced; she lives with her boyfriend in a Toronto apartment that’s pretty but has mice in the walls.

They fight about money, of which there is not enough. She cries a lot, worries about comma placement and has mother issues. She possesses a hard head and a large muse but cannot help but appeal to the rowdier gods — via psychics, tarot card readers and especially I Ching-inspired coin throws — for urgent answers to her pressing problems.

The most salient thing about her is that she does not, she is nearly certain, want a child. This unsentimental position puts her at odds with her friends. Indeed, it puts her at odds with North American and especially her Jewish culture, in which a burden is still placed on women to repopulate after the Holocaust.

About childbearing, she says: “It suddenly seemed like a huge conspiracy to keep women in their 30s — when you finally have some brains and some skills and experience — from doing anything useful with them at all.”