ON THE ELECTRODYNAMICS
OF MOVING BODIES

By A. Einstein
June 30, 1905

It is known that Maxwell's electrodynamics--as usually understood at the present time--when applied to moving bodies, leads to asymmetries which do not appear to be inherent in the phenomena. Take, for example, the reciprocal electrodynamic action of a magnet and a conductor. The observable phenomenon here depends only on the relative motion of the conductor and the magnet, whereas the customary view draws a sharp distinction between the two cases in which either the one or the other of these bodies is in motion. For if the magnet is in motion and the conductor at rest, there arises in the neighbourhood of the magnet an electric field with a certain definite energy, producing a current at the places where parts of the conductor are situated. But if the magnet is stationary and the conductor in motion, no electric field arises in the neighbourhood of the magnet. In the conductor, however, we find an electromotive force, to which in itself there is no corresponding energy, but which gives rise--assuming equality of relative motion in the two cases discussed--to electric currents of the same path and intensity as those produced by the electric forces in the former case. Examples of this sort, together with the unsuccessful attempts to discover any motion of the earth relatively to the "light medium", suggest that the phenomena of electrodynamics as well as of mechanics possess no properties corresponding to the idea of absolute rest. They suggest rather that, as has already been shown to the first order of small quantities, the same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good. We will raise this conjecture (the purport of which will hereafter be called the "Principle of Relativity") to the status of a postulate, and also introduce another postulate, which is only apparently irreconcilable with the former, namely, that light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body. These two postulates suffice for the attainment of a simple and consistent theory of the electrodynamics of moving bodies based on Maxwell's theory for stationary bodies. The introduction of a ``luminiferous ether'' will prove to be superfluous inasmuch as the view here to be developed will not require an "absolutely stationary space" provided with special properties, nor assign a velocity-vector to a point of the empty space in which electromagnetic processes take place.

For the morons such as Piggy Brown (PMB) and "Uncle" Bonehead Green Ph.D. (1956 Johns Hopkins) that can't comprehend plain language,

Principle of Relativity = relative motion with some suggestions tacked on!

What does wackypedia bluster?

Principle of Relativity ="The laws by which the states of physical systems undergo change are not affected."

What does Piggy Brown bluster?

Principle of Relativity = "the same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good."

What does this so-called Doctor of Philosophy, Ben Green of Schenectady, NY and one time lecturer at MIT, bluster?

Second postulate = "the speed of light is the same in all inertial frames of reference", a conclusion (and a reductio-ad-absurdum) from section IV.

Bungling incompetent IDIOTS seeking recognition from their fellow idiot peers!

And Einstein lies, his third postulate,

"the "time" required by light to travel from A to B equals the "time" it requires to travel from B to A" is crucial to the derivation of the cuckoo malformations,

where