|this will hurt me more than it will hurt you, son...|
Vaccine, vaccinate, vaccination, even, to some extent, our modern sense of the word virus are all due to this madman Edward Jenner. Seriously, give him a possible cure and he tested it on anyone he could get his hands on - prisoners, children, his own family, you name it! Louis Pasteur gave us a number of good words himself, which I'll have to tackle another time.
The third panel is based on an actual painting (which includes the cow at the window). It struck me as humorous, so I swiped it, as they say in cartooning circles. As you can see, I've gone gray-crazy. I got one too many enthusiastic responses, so it drove me to shading the hell out of the thing.