That's incomplete though; an asymmetric airfoil with 0° angle of attack does generate lift. The problem is the "equal times" -- the times are not "equal", but the air passing over the curved side does go faster.
Cambered airfoils generate lift at zero angle of attack. When the chord line is horizontal, the trailing edge has a downward direction and since the air follows the trailing edge it is deflected downward.
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The very short answer is that the wing pushes the air down, thus (by Newton's 3rd law) the air pushes the wing up.
That's incomplete though; an asymmetric airfoil with 0° angle of attack does generate lift. The problem is the "equal times" -- the times are not "equal", but the air passing over the curved side does go faster.
Sure. By deflecting the air down.
But the air on the leading edge is deflected upwards when it hits