  Has contemporary science enabled us to go beyond sensitive knowledge—have discoveries about compounds, elements, and subatomic particles provided us with knowledge of real essences? Much of the force of this question derives, to paraphrase Nicholas Jolley, from the fact that many of those discoveries about matter’s structure were not conceived empirically, but only confirmed empirically; they were initially conceived as possibilities by employing the hypothetico-deductive model, and the predictions deduced from the models were then compared to empirical data (Jolley 2002, p. 69). Yet as Jolley also points out, these commentators may have missed the full import of Locke’s geometric model; in a passage quoted earlier, Locke tells us explicitly that if we knew the real essence of gold, we could deduce its qualities even if gold did not  exist.[15] So while the predictions of any model developed via the hypothetico-deductive model must survive the test of observations, observations in Locke’s scientia are wholly unnecessary. To put the point another way, Locke takes natural philosophy to be an empirical domain only for human beings, with their impoverished faculties. For nobler spirits, it would more resemble geometry.