I, Master of Common Sense and Infallible Detector of Deception, had a weird adventure last evening. I went biking and at some point I passed one guy. A couple of minutes later the guy has passed me and, while doing so, informed me that I have dropped my wallet. My first thought was that it was extremely unlikely, as I was not in a habit of doing so, and last time that I lost a wallet was when I was 11 (I found it later intact). However, why would the stranger lie to me without reason? So I have spent next 10 minutes going through a complex reasoning in my head, imagining all possible ways for dropping the wallet and estimating the probabilities. This all to decide whether I should stop and check the wallet or not.
Suffice is to say that I have found dropping the wallet to be nearly impossible. It was possible that I had forgotten to fasten the zipper to the pocket in my backpack, where I keep the wallet while biking. It was also withing a realm of possibility that a hole was torn in the bottom or side of the backpack, or a seam has ripped. However the wallet was in the internal pocket, and other things would need to fall before it, specifically the cell phone or the metal wrench. Since it was all so improbable, I decided to ride to the usual resting place, and check the wallet there. So I did, and of course it was where it should be.
Now I am totally bewildered - first, how gullible I was, and second, why was the guy lying? Maybe he wanted me to stop and give him some breathing room? But this hypothesis is likely false, because racing another biker is a sure way to increase speed and improve the overall time, and so a desirable thing to do. Do you have any ideas that would explain that guy's weird behavior?