> Imagine you need to fly over a river to save your life, because you're being chased by a maniac with an axe. Would you fly? No, I would not - but if I surviv

> Imagine you need to fly over a river to save your life, because you're being chased by a maniac with an axe. Would you fly? No, I would not - but if I survive the encounter, I would learn to swim under highly controlled circumstances (i.e. while not being chased by a maniac), and swim an increasing number of laps to help my endurance. That way I may have confidence to swim across raging river, if my life involved having to borrow axes from strangers near rivers.