I put my grandmother's pendulum in a spreadsheet

Background: engineer, skeptic, but my farmor's brass pendulum has a strange track record in our family. So I ran an experiment.

Setup: 200 yes/no questions with answers I could check later (coin flips, sealed envelopes my sister prepared, next-day weather). Half the time I knew the answer while asking. Half the time I didn't.

Results: • When I knew the answer: pendulum 'correct' 91% of the time. • When I didn't: 52%. Basically a coin flip.

So the ideomotor effect is real, and my hands know what my head knows. Case closed, right?

Except here's the part I didn't expect. During the trials where I knew the answer, it started moving before I'd consciously decided anything, like it was showing me what I believed faster than I could think it. Which made me wonder whether my farmor was ever asking the pendulum to predict the future. Maybe she was asking it to tell her what she already knew, underneath the worry.

Last week I tested that the honest way. I'd been going back and forth on a job offer for days. Held the pendulum, asked 'Do I want this?' and it swung a hard yes before I'd even finished the sentence. I sat there laughing, because the spreadsheet would say that's just my own muscles. And yes. That's the point. I'd been ignoring them for a week.

I took the job. Farmor would have said 'I told you so' in Swedish, over coffee. Still a skeptic. Slightly less smug about it.