In religious politics he was equally liberal and advocated the separation of Church and State; the State, according to him, should not have any religion of its own, its province being only to protect equally the liberty of all denominations. Locke was discussed minutely by Leibnitz, who, without accepting the innate ideas of Descartes, did not accept the ideas through sensation of Locke, and said: "There is nothing in the intelligence which has not first been in the senses," granted ... "except the intelligence itself." The intelligence has not innate ideas born ready made; but it possesses forms of its own in which the ideas arrange themselves and take shape, and this is the due province of the intelligence. And it was these forms which later on Kant was to call the categories of the intellect, and at bottom Descartes meant nothing else by his innate ideas. Locke exerted a prodigious and even imperious influence over the French philosophers of the eighteenth century. CHAPTER IV THE ENGLISH PHILOSOPHERS OF THE EIGHTEENTH CENTURY Berkeley: Highly Idealist Philosophy which Regarded Matter as Non-existent. David Hume: Sceptical Philosophy. The Scottish School: Common Sense Philosophy. BERKELEY.--To the "sensualist" Locke succeeded Berkeley, the unrestrained "idealist," like him an Englishman. He began to write when very young, continued to write until he was sixty, and died at sixty-eight. He believed neither in matter nor in the external world. There was the whole of his philosophy. Why did he not believe in them? Because all thinkers are agreed that we cannot know whether we see the external world _as it is_. Then, if we do not know it, why do we affirm that it exists? We know nothing about it. Now we ought to build up the world only with what we know of it, and to do otherwise is not philosophy but yielding to imagination. What is it that we know of the world? Our ideas, and nothing but our ideas. Very well then, let us say: there are only ideas. But whence do these ideas come to us? To explain them as coming from the external world which we have never seen is to explain obscurity by denser darkness. They are spiritual, they come to us without doubt from a spirit, from God. This is possible, it is not illogical, and Berkeley believes it.