This morning I was getting ready for work and the thought occurred to me, "Did I lock up my bike last night?" I paused for a moment, and then I recalled pulling it inside and throwing my U-lock through the frame and locking it to the handrail anchored to the wall. I've done this hundreds of times. Then I walked into the living room and saw my bike sitting there. I thought for a moment and remembered how I'd brought my bike upstairs so I could adjust the brakes that were getting a bit squishy. Then I tried to remember if I'd gone to work yesterday, and if I had, did I spill a mug of coffee into the copy machine, or was that someone else?