This is from an interview to Charlie Kaufman, the director of the movie, which you can find here in its entirety:
I found a lot of similarities between Synecdoche and this novel, Remainder, by Tom McCarthy...
This script, for the record, [was] written before that novel came out. I saw a review of that thing [Remainder]; I was freaked out. I intentionally did not read it. I have not read it. I hadn’t made the movie yet, and I didn’t want to have any kind of influence [from] it. But like I said, this script was written before that came out. I saw it online and I thought, A) oh fuck, and B) this is a book that I would read, normally. This sounds like a cool book. But I won’t. And I haven’t. And I probably at some point I will, but I don’t know…now it might be awful to read it. It might be like, Oh, he had this great idea that I didn’t have and I cant do anything about it.
It’s interesting to know that you haven’t read it.
It’s an idea that…that idea is not new to me, in my work. This particular version of it…What I’m saying is, it’s an attractive idea. I would look at that novel and think, Oh, cool. But I couldn’t in this case.
It’s got a similar kind of self-contained illogic.
He builds an apartment house and hires actors?
[Sarcastically] I wonder if McCarthy read the script...
A few people left before the end of the screening. There were about fifteen-twenty people to start with, and the only person who really seemed to like the film was a guy sitting alone in the row in front of us and laughing at every joke, including the lame ones. We thought he was mad, but when the credits started rolling and we got up to go, we noticed there was a bunch of flowers in the seat next to his. He had been stood up.
Since this wasn't exactly the sort of movie you invite your date to, I think he deserved his fate.