This paper discusses recent attempts to use essentialist arguments based on the work of Kripke and Putnam to ground causal necessity in the world. I argue in particular that a recent argument by Alexander Bird relies on controversial intuitions about the natures of substances which no Humean would accept. While a case can be made that essentialism reflects some assumptions within scientific practice, the same can be said of Humeanism, and ultimately neither Bird’s arguments, nor any empirical facts, can decide the question either way