Postmodern theories on the subject are very diverse. In this article, we take a closer look at physicist and philosopher Karen Barad’s work in the emerging field of new materialism as an example of postmodern theory. The aim is to analyze Barad’s subject model as such and what it entails for doing the science of psychology. We will do this by analyzing Barad’s notion of the subject through three different types of subject models. This analysis will then be supplemented by a critical inquiry into Barad’s subject model by way of phenomenology. We conclude that Barad’s subject model is unfit for studying the subject in psychology as she leaves no room for the universal characteristic of experiential life, which makes it impossible to generalize psychological findings—a necessity in science—and that this criticism could apply to other subject models like hers in postmodern theory.