Person one: "How many pounds per square inch do I need to use in my legs in order to run to the store at an accelerated rate?"
Person two: "Just run. Breath, don't stress yourself out, keep an even pace. Remember to stretch first."
Person one: "OK, I have one of those leg-stretching machines, what should I set it for?"
Person two: "Just stretch until you feel comfortable and able to run."
Person one: "But how do I x so that I know I can z?"
Person two: "jus-" (Person two is suddenly cut off by a little green man wearing a heavy grey robe.
Little Green Man: "There is no try, only do or not do."
Person one: "But I'm afraid of doing it wrong."
Little Green Man: "Fear leads to anger. Anger leads to hatred. Hatred leads to suffering. Suffering is the path to the Dark Side."