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For history of medicine ‘down there’ see: https://pmc.ncbi.nlm.nih.gov/articles/PMC3223289/ Paragraph of interest begins thus: “The idea of...
@bisco that is a question worth thinking about. The following maybe be overstated, or a reflection on what I've seen where I've been. Here it is...
The difference is the existence of evidence. Not who says it.