Over the last two decades, philosophical discussions of special relativity have repeatedly focused on whether relativistic effects—most notably length contraction and time dilation—require a dynamical explanation or a kinematical one, or whether this binary choice should be abandoned altogether. Although this debate is primarily theoretical, advocates of the dynamical approach often appeal to historical considerations. In particular, it has been claimed that, while Einstein initially described length contraction and time dilation as merely apparent coordinate effects, he ultimately aimed to show that they reflect real physical changes in the equilibrium states of moving atomic systems. This paper challenges that historical narrative and argues that clarifying Einstein’s position bears directly on contemporary disputes concerning the dynamical–kinematical distinction. Continue reading →