Amy Tan was already at work on a novel when a photo turned the book, and her understanding of her family’s past, upside down. At an Asian art museum exhibit in Shanghai, Tan came across an illustration of courtesans entertaining men among Western furnishings. Inspired, she decided to include a courtesan in the novel. She bought a book on courtesan culture, and it was in this book that she found an illustration called “The 10 Beauties of Shanghai.”

“Five of these 10 beauties had clothes that were identical to what my grandmother had worn in my favorite photo of her, and I was stunned,” Tan says. She didn’t want to make assumptions—after all, she explains, Tan herself wears the clothes of a dominatrix when she plays with her band, the literary all-star Rock Bottom Remainders. Plus, the courtesans set fashion trends in China at the turn of the 20^th century, which everyone then imitated. But then a scholar told her that the clothes in the photo really were particular to courtesans.

“That sent me into a complete spin about what I had been told about my grandmother, who was supposed to be an old-fashioned, stay-at-home woman,” Tan says. “So then I thought, if that was true, what were the circumstances that led her there?”

And it was this question that inspired the central idea her new novel, The Valley of Amazement, explores: “It made me think about who we are as a result of our circumstances,” Tan says. “I’ve always been interested in questions of self-identity, how we see ourselves, which may be different than how society sees us or how our parents see us.”

Tan restarted the novel she’d already been at work on for more than four years. The first story was set in a remote Chinese village and dealt with the nature of accidents and responsibility. She took an element of that original story—a girl being separated from her mother and changing greatly as a result of her circumstances in the process—and applied it to her new obsession: the life of courtesans in Shanghai in the early 1900s.

It wasn’t hard for Tan to walk away from that initial version of the story, because she never feels like time spent writing is a loss. “Believe it or not, it’s not hard for me to part with things,” she says. “I think the best part of writing is the act of writing, actually being there and imagining things and playing with the words.”

Of course, she says, she cares about the receptions of her books (“I hope that I’m not humiliated”) and she wants them to sell well for the publisher. But the editing process never bothers her; nor does the fact that the first version of her book won’t be shared with readers: “I still have the experience of having written it. It’s not wasted; it’s still there. I have it written down, I have it in my experience.”

That healthy attitude toward darling-killing led Tan to cut more than 100 pages from The Valley of Amazement, under the gentle but confident direction of her editor, Daniel Halpern of Ecco. When asked if she was under pressure after the publication of her last novel, she laughs and responds that the reason for the eight-year gestation period between Saving Fish from Drowning and The Valley of Amazement is actually the opposite: “The problem is that I didn’t get a lot of pressure. I didn’t get a lot of people saying to me, ‘We must have it by this certain date.’ ” She was also working without an editor; after Faith Sale passed away in 1999, Tan says she was “scared to find another editor.” But two and a half years ago, she connected with Halpern, who had mentored under Sale, and that’s when the work sped up considerably.

If left to her own devices, Tan often tunnels into rabbit holes of research, most of which is motivated by curiosity. “It’s a flaw,” Tan says. “I have to stop because it gets obsessive. I want to know everything.” Case in point: When researching what toilets would’ve been like at the time, Tan found herself wondering whether toilet paper would’ve been used. She did some research and discovered that the Chinese actually invented toilet paper in A.D. 400. “I thought, ‘OK, this is too much,’ ” Tan says. “We don’t need to know all of that.”

Tan relied on library research, some Googling and travel to get the time and setting details right in the novel. She looked at a lot of photographs, she visited archives, she talked with people who’ve taken opium.

Her research is also often deeply connected to her own life. This novel is not autobiographical, but many elements of Tan’s life enter into it nonetheless: Her grandmother may have been a courtesan, which inspired much of the plot. Her grandfather took part in the 1911 revolution, which led to the 1912 overthrow of the Ching dynasty, and so the revolution makes its way into the story. He also died in the third wave of the Spanish influenza pandemic; that too is woven into the story. But it’s not just history that creeps in: “All the bad men [in the book] are modeled after my mother’s first husband.” And Tan draws from her own life as well. A harrowing scene in the book comes straight from Tan’s own experience of being nearly impaled by a rock when climbing the Great Wall.

In fact, Tan says, her fiction encompasses much of her life, even if the correlations are not direct. “I incorporate what happens almost daily,” she says. “It’s like a little diary to myself, that whole act of writing and just incorporating who I am that day and what happened, and it’s my little diary that I was alive and I had these thoughts on this day at that time, and that’s why it’s wonderful to write.”

Jaime Netzer is a writer and editor living in Austin, Texas. Her fiction has been published in Twelve Stories and Corium Magazine and is forthcoming in Parcel. She’s at work on her first novel.