John Locke was not the first seventeenth-century philosopher to attempt to find a place for morality and politics within the framework of the emerging science, without final causes. No doubt the most original and influential in this respect was Thomas Hobbes. Indeed, Hobbes calls moral philosophy itself a science, the “science” of good and evil. Since he insists that English language users invariably employ ‘good’ and ‘evil’ simply to refer to objects of their desires and aversions, respectively – there being no “common rule of good and evil, to be taken from the nature of the objects themselves” – Hobbes holds that ethics can equivalently be defined as the science whose subject is “consequences from the passions of men” (Lev.vi.7; IX.4). Simplifying greatly, ethics is the subject that works out what people should do from premises about their desires and aversions, that is, from what they hold to be good and evil.

At the same time, Hobbes also says that “the true and only moral philosophy” is the science of the laws of nature (Lev.xv.40). This invites the obvious question of what earns something the status of law, and precisely what this status is. Sometimes – for example, in his initial statements of the right of nature and definition of a law of nature – it can seem as if Hobbes is simply assuming fundamental normative truths, whose normativity he takes for granted as additional to anything science might discover about human beings, their passions, and their situation vis-à-vis another.