An example is considered (clock riddle) which demonstrates that opposite results
are obtained for the length of an object depending on whether FitzGerald-Lorentz
contraction (FLC) is assumed or instead the determination is based on the elapsed
time required for a light pulse to traverse between its endpoints. This lack of
internal consistency in relativity theory is traced to an undeclared assumption
Einstein made regarding a normalization factor appearing in his original
derivation of the Lorentz transformation (LT).