“Do you believe in ghosts?” As the author of a book entitled How to Build a Haunted House: The History of a Cultural Obsession, it’s a question I get asked a lot. My answer is “Perhaps,” as unexpected as it is unsatisfying. The truth is, I don’t know.

Why do some houses set our super-sensory alarm bells jangling, while others leave us unmoved? Is there a particular set of ingredients—aesthetic, historical, cultural, or otherwise—that can combine to create the “haunted house” of our collective imagination? These were the questions I sought to answer in the book. It was never my intention to sway readers one way or another in regard to the actual existence of ghosts. However, I do acknowledge that the prospect that undead spirits walk among us is an irresistible one. And while I can provide no hard evidence to support either side, I can offer up a personal anecdote which some readers might interpret as a supernatural encounter.