From the other thread.
Newtons laws apply equally to both sides of the wing and explain the velocity differences. Bernoulli, while useful in some cases, is more of a red herring when it comes to explaining lift.
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A longer version, but by an actual expert
I have recently been reading "An Introduction to Flight" by Anderson, which is a sophomore level college textbook in aerodynamics.
What the Capt. says here is fundamentally true. Lift is generated by the different pressure distributions on the top and bottom of the wing, which are explained by and can be derived from Newton's laws applied to a fluid. Bernoulli's law can be derived from those underlying physical laws. It is also true that fluids flow faster in areas of lower pressure.
In aviation training, I have noticed that instructors use a number of rough approximations of these ideas to explain the generation of lift, induced drag, ground effect, etc. That is not necessarily a bad thing per se given that many students may not have had calculus, or if they did, it was a long time ago. But I think these simplifications give rise to troubles in teaching for 2 reasons:
1. They are often not qualified appropriately as such and with proper reference to the true underlying physical principles. For example, one can say "The lift on the wing is generated by a difference in the pressure distributions between the top and the bottom of the wing which are created by the air flowing over the wing. While these are complicated to compute in exact form, here is a simplified way to think about it...". Then the student understands that the little cartoon is not a full physical explanation, but rather a cartoon to help understanding.
2. Many instructors and examiners have their preferred cartoon way of dealing with this and seem to forget that these are just rough approximations and also are convinced that all other approximations and cartoons are just flat out wrong. Of course, in many cases, they are probably just inaccurate approximations in a different way.
Personally I think the cartoons can be useful, so long as they are used as such. Our flight students are not often going to want or need an aeronautical engineering level of understanding. What they will need is some sort of mnemonic device to help them remember the main effects, such as AoA and stalls, DA, etc. and the ability to pass the FAA exams.
