The origin of Herbal & Natural Medicine were gods, demigods, rishis, emperors, immortals, ancestors & other exalted beings.
This is true for Egyptian, Greek, Ayurvedic, Chinese, Native North American, Native South American, African & other traditional medicine systems.
From these origins all traditional medicine developed in oral & literate traditions along to present times.
Evidence Based Medicine (EBM) is a form of empirical knowledge based medicine that places a template of conditions to validate or invalidate traditional knowledge. As EBM is lacking a basic energetic understanding of plants it can never explain most traditional knowledge and must eliminate from its purview that set of understanding.
In other words, EBM can only explain material phenomena and metabolic pathways that can be measured by machines & chemistry labs.
No machine can find acupuncture points or meridians, measure Qi, prana nor Vis and yet this universal life energy is the foundation of holistic herbal medicine.