the flea's question

One afternoon, while a flea as talking to an ox, working in the field, the flea curiously asked him, “Why is it, that while you are so big and strong, you serve men day after day, while I, because I am so small a creature, drink their blood and feed on their flesh?” The ox answered him, “I am well loved by strong, friendly men, who pat me on my head and shoulders all the time.” The flea unbelievingly then replied, “While you like this patting, whenever this same thing happens to me, it brings me great sorrow and destruction!”