Did Einstein really discover "E = mc2"?, W.L. Fadner, Am. J. Phys., 56(2), February 1988
In 1952, Herbert Ives claimed that Einstein's first development of E = mc2 was circular, and that he had not been the first to develop that equation. That allegation has been repeated in several more recent works. Earlier, Planck asserted that one of the postulates that Einstein had used in that development was not exact. Those claims and subsequent papers concerning them are examined herein. The surprisingly long history history of the mass-energy relation is summarized. In the context of this topic, it is argued that circularity is seldom a legitimate critique of scientific proposals. A simple refutation of Planck's claim is also included.