I don't think that many thoughts are derivative. One certainly doesn't learn thinking by imitation, at least in early childhood and not directly in later life s

I don't think that many thoughts are derivative. One certainly doesn't learn thinking by imitation, at least in early childhood and not directly in later life stages. Yes, many "library-like" algorithms (those for simple and narrow, well-understood tasks) are derivative, but there is much other thinking - "fluid" thinking as a whole, and also many particular small tricks / heuristics that are discovered independently by many smart individuals.