no older (I say it provoked, and that my detractors may know how little they have wrought upon me) than my own book _De Cive_. But what? were there no philosophers natural nor civil among the ancient Greeks? There were men so called; witness Lucian, by whom they are derided; witness divers cities, from which they have been often by public edicts banished. But it follows not that there was _philosophy_. There walked in old Greece a certain phantasm, for superficial gravity, though full within of fraud and filth, a little like philosophy; which unwary men, thinking to be it, adhered to the professors of it, some to one, some to another, though they disagreed among themselves, and with great salary put their children to them to be taught, instead of wisdom, nothing but to dispute, and, neglecting the laws, to determine every question according to their own fancies. The first doctors of the Church, next the Apostles, born in those times, whilst they endeavoured to defend the Christian faith against the Gentiles by natural reason, began also to make use of philosophy, and with the decrees of Holy Scripture to mingle the sentences of heathen philosophers; and first some harmless ones of Plato, but afterwards also many foolish and false ones out of the physics and metaphysics of Aristotle; and bringing in the enemies, betrayed unto them the citadel of Christianity. From that time, instead of the worship of God, there entered a thing called _school divinity_, walking on one foot firmly, which is the Holy Scripture, but halted on the other rotten foot, which the Apostle Paul called _vain_, and might have called _pernicious philosophy_; for it hath raised an infinite number of controversies in the Christian world concerning religion, and from those controversies, wars. It is like that _Empusa_ in the Athenian comic poet, which was taken in Athens for a ghost that changed shapes, having one brazen leg, but the other was the leg of an ass, and was sent, as was believed, by Hecate, as a sign of some approaching evil fortune. Against this _Empusa_ I think there cannot be invented a better exorcism, than to distinguish between the rules of religion, that is, the rules of honouring God, which we have from the laws, and the rules of philosophy, that is, the opinions of private men; and to yield what is due to religion to the Holy Scripture, and what is due to philosophy to natural reason. And this I shall do, if I but handle the Elements of Philosophy truly and clearly, as I endeavour to do. Therefore having in the Third Section, which I have published and dedicated to your Lordship, long since reduced all power ecclesiastical and civil by strong arguments of reason, without repugnance to God's word, to one and the same sovereign authority; I intend now, by putting into a clear method the true foundations of natural philosophy, to fright and drive away this metaphysical _Empusa_; not by skirmish, but by letting in the light upon her.