“I shan’t bore you by explaining [the] carbuncles on my posterior and near the penis, the final traces of which are now fading but which made it extremely painful for me to adopt a sitting and hence a writing posture. I am not taking arsenic because it dulls my mind too much and I need to keep my wits about me.”

“The bourgeoisie will remember my carbuncles until their dying day,"

— letter from Marx to Engels in 1867.