For about a month now I could feel a splinter in the sole of my left foot. The sharp pain was fleeting; I could only feel it when I stepped in a particular way. Pressing the skin of my sole with my fingers yielded no clues as to the precise position of the splinter. On several occasions I examined my foot immediately after I felt the pain, using the proprioceptive neural stimulus to home in to the entry wound. On several occasions I thought I had found it. On several occasions I took to my foot with my penknife, digging for the offending foreign body. On all occasions the excavations were fruitless.

Then, last night, after a day of increased splinter sensing, a dark thought from my subconscious started crawling past the consciousness threshold. Before it was even halfway across, I had my left flip-flop in my hands, kneading it with my thumbs. And therein the splinter had been all this time, embedded deeply in the black rubber of my supposedly protective appendage, pricking my foot every time I stepped down onto it. Of course I had been feeling it more: I was wearing those flip-flops all day. Out came the penknife and out came the splinter.

I am convinced this is a good parable for something, but damn me if I know what that is.