> Now, some answers to why wings work are just plain wrong (like the original wrong answer -- the Bernoulli effect). However, when one person says "Wings work because they push air down, and the air pushes the wing up", and another person yells "No, that's all wrong! It's because of <insert-fancy-effect-here>", they can both be right
But arguably "Wings work because they push air down, and the air pushes the wing up" doesn't really answer the question because air being pushed down is as much an effect of wing working as is airplane flying, but the cause why wing works would remain mystery.
You: "But that doesn't answer the question. WHY does the air get pushed down?"
They: "Because of such-and-such effect..."
You: "But that doesn't answer the question. WHY does such-and-such effect happen?"
They: "Because of fluid viscosity and boundary layers and navier-stokes blah blah blah..."
You: "But that doesn't answer the question. WHY does fluid have viscosity?"
They: "Because a such-and-such bonds between the molecules of the fluid..."
You: "But WHY..."
But arguably "Wings work because they push air down, and the air pushes the wing up" doesn't really answer the question because air being pushed down is as much an effect of wing working as is airplane flying, but the cause why wing works would remain mystery.