The blindfolded donkey.
Student Leaf approached Master Stem with a question. “Master Stem. My statistical model requires an assumption of normality, but I have an outlier in the data. Should I not remove the outlier so I can satisfy this assumption?”
Master Stem replied, “It is a perilous journey you are undertaking and I understand your caution. When I last crossed the mountains, I was also cautious. The donkey I rode upon knew the path well, but during the most dangerous part of the journey, I blindfolded him because if he could not see the loose rocks on the path, he would not slip on them.”