The Spirit of the Laws begins with a short Foreword (added in 1757) followed by a Preface. In the Forward, Montesquieu briefly defines virtue. As he will subsequently make clear in Book 1, virtue is the principle, or “spring,” by which the republican form of government acts. Virtue is the “love of the homeland” (xli) a love Montesquieu equates with love of “equality.” This is neither a religious nor a moral virtue; it is a political virtue. He notes that anytime he refers to “virtue” in the book, it will always be with regard to political virtue. Montesquieu, keenly aware of his audience, and personally a subject of the French monarchy, makes clear that he in no way means that virtue is absent from monarchies; in monarchies, virtue may or may not be present to varying degrees. The principle of a monarchy is honor, not virtue.

In the Preface, Montesquieu humbles himself before his reader, explains the difficulty with which he composed The Spirit of the Laws over decades of research, and asks that his audience refrain from judgment until they’ve closely examined the work.