Open the pores and bad humors will go in..? Just what kind of logic...
I'm going to read some literature about medical technology of medieval times :/ so weird.
@hazzack I think they are not using one particular European country as reference. Ain't like hot water bathing has existed has been known in Japan forever and hot springs are not common in much of Europe to my knowledge. I just think of this as comparing common things of today and back then. Japan was tamed long before Europe though the people weren't always tame back then in Japan.
If the land is not tame then the people can't be tame either.
I assume he's saving "LET'S MAKE JAPANESE MAYONAISE" for when they are saving a pastry chef who made too good sweets. Or accidentally baked bread laced with LSD, which would be way more "historically correct" when it comes to false witch accusations.