It’s no accident that the main characters of several of the stories in Filter House are children, and parenting is central to others. Nisi Shawl is an elder who sits the reader down and says "Listen to this story, child, and learn from it." The didactic nature of the stories doesn’t make them dull, at all, and neither (with a couple of exceptions) are they so simple that you feel you’ve gotten all you can get out of them with one reading. The imitation folktales that open and close the collection are some of the best examples of that genre I’ve ever found. In general, ambiguity is not Shawl’s method, but subtlety is. However, I think "The Water Museum" is genuinely ambiguous (and "But She’s Only a Dream" was confusing, which is a different matter). They are also all serious, without many laughs, in spite of the presence of trickster characters. This is not a real weakness, though -- very rarely does it seem that Shawl is trying for humor and failing. In general (with maybe one or two exceptions), I thought this collection ranged from good to excellent.