A study of the published and unpublished parts of Ernst Mach's last notebook (1910–14) suggests that Max Planck's attack (1908–11) provoked Mach into opposing ‘The Church of Physics’ more strongly than previously realized. Shortly after Mach threatened to leave the discipline if belief in atoms were required. Albert Einstein tried to persuade him to accept atomism (September 1910). Mach declined to mention Einstein again in his publications and increasingly criticized ‘The Church of Physics’. Evidence that Mach opposed relativity theory and the absence of evidence that he favored it is pointed out. It is suggested that Mach's alleged ‘friendly interest’ in Einstein's work in early 1914 may have been stimulated by the hope that the young genius might develop a continuum or field theory to refute Planck's discontinuity physics. The paper concludes with suggestions on how philosophers who defend Mach's non-realism such as Gereon Wolters and Paul Feyerabend might be better off switching to a realist epistemology more compatible with rationally-held science, religion, and common sense.