The chapter discusses the issue of how we may achieve knowledge of essence. It offers a critical survey of the main theories of knowledge of essence that have been proposed within contemporary debates, particularly by Lowe, Hale, Oderberg, Elder, and Kment.

Constitutivists often argue that agency is inescapable. This is supposed to, among other things, explain why norms that are constitutive of agency are forceful. But can some form of inescapability do that? I consider four types of inescapability—psychological, further factor, standpoint, and plight—and evaluate whether they manage to explain four necessary features of normative force: that it does not vary with desire change, that ought-implies-can and can-fail, and that we are criticizable for failing to live up to forceful norms. The (...) former three all fail to explain some of these features, but a version of plight inescapability does, in fact, appear able to explain them all. This is good news for constitutivists. The catch? The plight inescapability explanation generates relativism. This leaves constitutivists at a choice point: accept the plight inescapability explanation of normative force and relativism—or give up the plight inescapability explanation. (shrink)