After that unsettling medical adventure, I began mulling over why I was so disturbed to see the insides of my body. A number of issues come to mind. For starters, the experience struck me as a vivid demonstration of my materiality. Even though I am a scientist and have a materialist view of the world, I still harbor the belief that I am more than just a jumble of tissues and nerves. The experience of consciousness and life is so sublime that it is hard to imagine it all arising from mere atoms and molecules. And with that unwelcome materiality of my person came a new revelation of my mortality. All material things eventually disintegrate and pass away. That is the unbending law of the material world. In time, wood rots, paint peels, mountains reduce to powder and stone. Despite my hopes and illusions, the view of my colon forced me to remember that I am just material stuff, doomed to disintegration and demise.