Because the term “diversity” has two related but different meanings, what authors mean when they use the term is inherently unclear. In its broad form, it refers to vast variety. In its narrow form, it refers to human demographic categories deemed deserving of special attention by social justice–oriented activists. In this article, I review Hommel’s critique of Roberts et al. (2020), which, I suggest, essentially constitutes two claims: that Roberts et al.’s (2020) call for diversity in psychological science focuses exclusively on the latter narrow form of diversity and ignores the scientific importance of diversity in the broader sense, and ignoring diversity in the broader sense is scientifically unjustified. Although Hommel’s critique is mostly justified, this is not because Roberts et al. (2020) are wrong to call for greater social justice–oriented demographic diversity in psychology but because Hommel’s call for the broader form of diversity subsumes that of Roberts et al. (2020) and has other aspects critical to creating a valid, generalizable, rigorous, and inclusive psychological science. In doing so, I also highlight omissions, limitations, and potential downsides to the narrow manner in which psychology and the broader academy are currently implementing diversity, equity, and inclusion.