Einstein's constant-speed-of-light postulate, in its implication that the speed of light is independent of the speed of the observer (the same for all observers), was (and still is) obviously idiotic:
John Stachel: "But this seems to be nonsense. How can it happen that the speed of light relative to an observer cannot be increased or decreased if that observer moves towards or away from a light beam? Einstein states that he wrestled with this problem over a lengthy period of time, to the point of despair." http://www.aip.org/history/exhibits/einstein/essay-einstein-relativity.htm
So Einstein had to devise some mythology justifying the introduction of the idiocy. Here is the mythology:
1. The idiocy was a tenet of Maxwell's 19th century electromagnetic theory.
2. The idiocy was confirmed by the Michelson-Morley experiment.
Brainwashers in Einstein's schizophrenic world know that teaching Einstein's mythology is vitally important:
Brian Cox, Jeff Forshaw, Why Does E=mc2?: (And Why Should We Care?), p. 91: "...Maxwell's brilliant synthesis of the experimental results of Faraday and others strongly suggested that the speed of light should be the same for all observers. This conclusion was supported by the experimental result of Michelson and Morley, and taken at face value by Einstein." http://www.amazon.com/Why-Does-mc2-Should-Care/dp/0306817586
Leonard Susskind: "One of the predictions of Maxwell's equations is that the velocity of electromagnetic waves, or light, is always measured to have the same value, regardless of the frame in which it is measured. [...] So, in Galilean relativity, we have c'=c-v and the speed of light in the moving frame should be slower than in the stationary frame, directly contradicting Maxwell. Scientists before Einstein thought that Galilean relativity was correct and so supposed that there had to exist a special, universal frame (called the aether) in which Maxwell's equations would be correct. However, over time and many experiments (including Michelson-Morley) it was shown that the speed of light did not depend on the velocity of the observer measuring it, so that c'=c." http://www.lecture-notes.co.uk/susskind/special-relativity/lecture-1/principles-of-special-relativity/
Brian Greene, The Elegant Universe, p. 19: "If she fires the laser toward you - and if you had the appropriate measuring equipment - you would find that the speed of approach of the photons in the beam is 670 million miles per hour. But what if you run away, as you did when faced with the prospect of playing catch with a hand grenade? What speed will you now measure for the approaching photons? To make things more compelling, imagine that you can hitch a ride on the starship Enterprise and zip away from your friend at, say, 100 million miles per hour. Following the reasoning based on the traditional Newtonian worldview, since you are now speeding away, you would expect to measure a slower speed for the oncoming photons. Specifically, you would expect to find them approaching you at (670 million miles per hour - 100 million miles per hour =) 570 million miles per hour. Mounting evidence from a variety of experiments dating back as far as the 1880s, as well as careful analysis and interpretation of Maxwell's electromagnetic theory of light, slowly convinced the scientific community that, in fact, this is not what you will see. Even though you are retreating, you will still measure the speed of the approaching photons as 670 million miles per hour, not a bit less. Although at first it sounds completely ridiculous, unlike what happens if one runs from an oncoming baseball, grenade, or avalanche, the speed of approaching photons is always 670 million miles per hour. The same is true if you run toward oncoming photons or chase after them - their speed of approach or recession is completely unchanged; they still appear to travel at 670 million miles per hour. Regardless of relative motion between the source of photons and the observer, the speed of light is always the same." http://cfile205.uf.daum.net/attach/141EBD484EE5A30219CDD4