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In other words, I think the distinction between the two alternate explanations is imaginary. It's the Third Law at work, but Bernouli explains the details.

This all started because I took exception to the statement that a "propellor pushes" against the air/water. A commnon statement that leads the uneducated to believe that you must "push against" something to get thrust. That is, the water that is accelerated by the propellor has to push against more water in order to provide thrust. This concept leads to the next question; "Gee, how does a rocket work in space if there is "nothing to push against?"

Now we have Mr. Physicist so enraged that he is making statements such as "propellors have no airfoil effect"!

A common misconception by laymen is that the force is derived from "pushing against" the water/air as in pushing against a wall. In reality, the force is derived from the acceleration of the water/air. The force would be the same in a vacuum for the same amount of water/air accelerated even though there would be no air/water to push against.
78 -cinFLA-

The issue:

"The propellor or the jet engine of an aircraft push air backwards to propel the aircraft forward. A ship or boat propellor does the same thing with water. On Earth there is always air or water available to push against. But a rocket in space has nothing to push against, and so it needs to carry propellant to eject in place of air or water."
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Perfectly simple point made above.
-- If you are on the ground you can push against it to move.
-- If you are in the water you can push against it to move.
--- If you are in the air you can push against it to move.
--- If you are in space you can't push against it to move, you must eject something away from you.

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Now you claim:

"This all started because I took exception to the statement that a "propellor pushes" against the air/water."
-cin-

As we see above, you can't keep your story straight on ANYthing.

Let's look at an example: Say I'm out in space, with a large rock in my arms, and I throw the rock off in a certain direction. I would of course start moving in the opposite direction. Was I not "pushing" against the rock?