It’s Halloween time, so as one would expect, many ghostly happenings have been … happening.

A few nights ago I had a lovely date night with myself. I got some snacks and some wine, turned off all the lights except for a single candle, and sat down to watch a scary movie. I’d never seen The Changeling before, but it had a few rare moments of freaking the hell out of me with its simple but effective scares. It’s all the ghost story clichés done right.

Then today, at the Central Library, I went to see a talk by ghost researcher Cameron Bagg, who presented these same ghost clichés as fact. It was an interesting presentation; he told the story of how he first encountered ghosts (mysterious sounds, feeling a presence, teleporting objects, etc.), the tools he uses to hunt ghosts, some spooky anecdotes, all that. He showed some pictures of ghosts and spirit orbs. Ambiguous shadows and spheres of light.

At strange gatherings like this, I find the audience makeup and reactions as fascinating as the talk itself. This was a diverse group of people – old, young, crazy, not-crazy. Good old Roy McDonald was in attendance (he seems to be everywhere at once … like a ghost). And their reactions; well, I think this was the defining moment:

Bagg took out a television remote control. A regular remote, with an infrared transmitter on the end. He pointed it at the audience, clicked a button a few times, and said “does everyone see the flashing light?”

Many in the audience nodded. Murmurs of “ah, yes!” and “I see it!”

But there was no flashing light. His point was that cameras can see frequencies of light that are invisible to the naked eye (e.g., infrared; indeed, a flashing light could be seen when he pointed it through a camera). But there is a deeper point that inadvertently came out: when people are presented with a suggestion, they are likely to see things as consistent with that suggestion. When shown a static bulb and told it was flashing, many people in the audience, they literally thought they saw it flashing.

Similarly, when someone believes she is about to see ghost photographs, then you show her a shapeless shadow, she will see a human figure in it. Suggest that a dead woman lived in a house, and a picture of an empty room contains her face in a blob of reflected light. The noises at night aren’t the people in the next apartment bumping around, but ghostly rapping. An object appearing where it shouldn’t isn’t a lapse in memory, but a mischievous poltergeist.

I’m not saying ghosts aren’t real. Ghosts are an intense phenomenon genuinely experienced by a significant proportion of the population. These experiences can’t be explained by the speculations of armchair debunkers, and even though I wish he was more objective about it, I am glad that people like Cameron Bagg are out there actually trying to figure it out. But aside from any paranormal explanations, there is a lot of equally fascinating normal human psychology going on in the minds of those looking for ghosts.