Universal laws of physics. Specifically, highs (high pressure) seek lows (low pressure). Remove a valve stem and the air flows out of the tire or inner tube. Why? Because the high in the tire/tube seeks the low outside the tire/tube. If there is a high over Dayton on the weather map and a low over Toledo the wind in Lima will be out of the south. Why? Because the high in Dayton is seeking the low in Toledo so the air flows north. The high under a wing (caused by deflection) will seek the low above a wing (vacuum) and the wing will move up (lift). The high will seek the low but the wing is between them. Moving the wing up, because highs seek lows, is lift. This may be an over simplification, but universal laws of physics do not change (ie: at 5252 rpm torque and HP are ALWAYS equal).