Law, properly, is the word of him, that by right hath command over others.Hobbes, Leviathan, ch. 15
Lex est mandatum ejus personae, sive hominis sive curiae, cujus praeceptum continet obedientiae rationem.De Homine, ch. 14, 1
THE LAW IN GENERAL AND ITS SPECIFICATIONS
‘Law, properly, is the word of him, that by right hath command over others.’ Such is the unified concept that Hobbes gives of the law in general. The difference between laws, in particular the difference between natural law and civil law, derives from the specification of the term left undetermined in the general definition. In order to pass from this definition to particular laws, it is in fact sufficient to specify the name of the legislator. Thus, natural law is characterised as ‘the word of God, that by right commandeth all things’, and civil law considered as adding nothing to the general concept of the law other than ‘the name of the person Commanding, which is Persona Civitatis, the Person of the Common-wealth’. The Elements of Law already indicated it – ‘From the difference of the authors, or lawmakers, cometh the division of law into divine, natural, and civil’ – before recalling in the following paragraph that natural law and divine law are a single law.
The definition of the law in general is composed of two principal determinations: on the one hand, the notion of a right to command which belongs to a legislator; on the other hand, the indication of a mode of signifying. To these two general determinations is added a third, the specification of the legislator, who intervenes in order to specify the kind of law.
First, in the definition of the law, the notion of command is fundamental. It is what assures the unity of the concept but also its limitation. The law returns to a relation of obligation between persons. It is thus neither, in an old sense, a principle of action that immanently governs beings, nor, in a modern sense, a necessary relation between phenomena. As command, the law is indeed the declaration of one person's will to another who must obey him.