Generally conducted by homeopathy practitioners and advocates, rather than scientists, the emphasis of provings has always focused on determining accurate symptom profiles. These are then applied homeopathically in clinical practice – according to the law of similars. But significant questions arise as to their quality, and the inconsistencies in approach and method remains at issue for 19th, 20th and 21st century provings. For the vast majority of these experiments the fundamental hypothesis has been, ‘what symptoms and conditions might this substance be useful for’? But what about re-provings? Comparative evaluation of the data extracted from old and modern provings can reveal significant similarities. This paper explores a model of comparing subjective symptoms from provings which if robust enough challenges the idea that homeopathic responses are placebo. For example, a significant overlap of symptoms from a proving of Culex was noted compared to a previous one. Conducted in 2004 with sound design and method, the data is compared to a proving of Culex conducted in the 1800’s, more than 100 years apart. Repeated improved provings with better design, ethics approval and method have subsequently been conducted on substances from Chamomilla, Tuberculinum, Blatta orientalis to Kangaroos Milk. This paper explores four different points.