Another famous article from the past: P. W. Anderson “More is different” 50 years ago
… the next stage could be hierarchy or specialization of function, or both. At some point we have to stop talking about decreasing symmetry and start calling it increasing complication. Thus, with increasing complication at each stage, we go up on the hierarchy of the sciences. We expect to encounter fascinating and, I believe, very fundamental questions at each stage in fitting together less complicated pieces into a more complicated system and understanding the basically new types of behavior which can result.