 Though Occam’s Razor has arguably been a longstanding and important tool in the rise of analytic metaphysics, it has only been comparatively recently that there has been much debate among metaphysicians concerning the principle itself. Cameron (2010), Schaffer (2010), and Sider (2013) each argue for a version of Occam’s Razor that focuses specifically on fundamental entities. Schaffer (2015, p. 647) dubs this version "The Laser" and formulates it as an injunction not to multiply fundamental entities beyond necessity, together with the implicit understanding that there is no such injunction against multiplying derivative entities. Baron and Tallant (2018) attack ‘razor-revisers’ such as Schaffer, arguing that principles such as The Laser fail to mesh with actual patterns of theory-choice in science and are also not vindicated by some of the lines of justification for Occam’s Razor.