Leonard Susskind discovered the syllogism of the Einstein-Feynman hoax (perhaps the correct name is "Einstein-Feynman-Susskind hoax"):

Premise 1: The laws of physics are the same in every inertial frame (principle of relativity).

Premise 2: The speed of light is a law of physics - Einstein said so.

Conclusion: The speed of light is the same in every inertial frame.

Leonard Susskind: "The principle of relativity is that the laws of physics are the same in every reference frame. That principle existed before Einstein. Einstein added one law of physics - the law of physics is that the speed of light is the speed of light, c. If you combine the two things together - that the laws of physics are the same in every reference frame, and that it's a law of physics that light moves with certain velocity, you come to the conclusion that light must move with the same velocity in every reference frame. Why? Because the principle of relativity says that the laws of physics are the same in every reference frame, and Einstein announced that it is a law of physics that light moves with a certain velocity." https://youtu.be/toGH5BdgRZ4?t=626

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