This chapter serves as an introduction to the polemical dismissal of Epicurean teachings as sub-masculine and morally suspect. Epicureans are shown to figured as sexually receptive and effeminate by their ideological opponents. I argue that Lucretius accepts these criticisms and turns them around to show that Roman men are equally effeminate and penetrable. Objective, empirical observation of nature and physics proves that everyone, regardless of biological sex and sociological gender, is rendered penetrable and vulnerable by the constant issue and reception of atoms.