The evolution of Traditional Chinese Medicine as recombinant inventions.

It has been widely recognized that technologies evolve with recombinant inventions. However, it remains unknown whether technologies developed using different approaches would exhibit different features during evolution. In particular, would technologies developed mainly based on accumulated experience in practices-formulas of traditional Chinese medicine (TCM) are typical examples of such technologies-have similar evolution features found in modern technologies? This study applied network science to explore the evolution of TCM from the perspective of recombinant inventions based on 59,063 TCM formulas documented over the last two thousand years, with each formula being a combination of components that are mostly herbs. Our results show that similar to modern technological systems, the TCM component networks maintained the core-periphery structures during evolution, and the (weighted) degrees of components followed heavy-tailed distributions. Moreover, simple tuples, which are frequently used combinations of TCM components, serve as building blocks for complex ones. A significant difference with modern technological systems is that the TCM core components were quite stable, while substitutions of core components are frequently observed in modern technological systems, leading to new technological trajectories. TCM comprises ancient knowledge and wisdom. This research provides insight into how it will be like in the future and what is important for its future.