Just to add, when Lister introduced antiseptic methods he was met with strong resistance from those same doctors who were equal parts annoyed with the messenger, and the message. It’s a hard thing to realize that you’d be killing thousands of people in your ignorance after all. It took quite a long time for his methods to be widely accepted and put into practice. Even when understanding emerges, you have to watch out for the entrenched interests defending themselves against change.