Systems of Complexity

If we were to replace our bodies, one atom at a time, would we be the same person? One would think this would be the case. Every 10 years, every cell in our body will have been replaced at least once, with bone marrow taking the longest to renew. Most of the body renews every 7 years. Our bodies are an ecosystem not unlike any other. Take the sea – remove and replace it one atom at a time and no fish will notice. Replacing larger pieces will cause problems for its inhabitants, but it will soon renew itself. Replace a large proportion, and this will likely have huge implications for the entire ocean. As it is with humans, replacing one small section at a time would be easily accounted for and would not have any dramatic effect on the system as a whole. This is a dramatic realisation – for what are we if not our bodies? We are not single entities. We are systems, and we are made from smaller systems, which in turn are made from smaller systems. Cells take in matter from our food