I have not been practicing the guitar much at all, but the fingertips of my left hand have toughened up nonetheless. I had not realized how much until yesterday. I was slicing a cucumber, clumsily, and nearly put the knife into my finger. Instead the blade bounced off, and no damage was done. It took me a minute to process that. I thought of my therapy clients, one in particular, and a moment she shared with me where something that might have wounded her bounced off instead, because of work we had done together, because now she was able to see the knife coming, and because something in her had toughened, or wisened somehow. It made me smile, the thought of that knife not piercing the changed skin.