Campanella, likewise an Italian, who spent twenty-seven years in a dungeon for having conspired against the Spanish masters of his country, and who died in exile in Paris in 1639, was a sceptic in philosophy, or rather an anti-metaphysician, and, as would be said nowadays, a positivist. There are only two sources of knowledge, observation and reasoning. Observation makes us know things--is this true? May not the sensations of things which we have be a simple phantasmagoria? No; for we have an internal sense, a sense of our own, which cannot deceive us, which affirms our existence (here is the _Cogito_ of Descartes anticipated) and which, at the same time, affirms that there are things which are not ourselves, so that coincidently the ego and the non-ego are established. Yes, but is this non-ego really what it seems? It is; granted; but what is it and can we know what it is? Not without doubt, and here scepticism is unshakable; but in that there is certitude of the existence of the non-ego, the presumption is that we can know it, partially, relatively, very relatively, while we remain infinitely distant from an absolute knowledge, which would be divine. Therefore let us observe and experiment; let us make the "history" of nature as historians make the history of the human race. And this is the simple and solid philosophy of experiment. But Campanella, like so many more, was a metaphysician possessed by the devil of metaphysics, and after having imperiously recommended the writing of only the history of nature, he himself wrote its romance as well. Every being, he said (and the thought was a very fine one), exists on condition of being able to exist, and on condition that there be an idea of which it is the realization, and again on condition that nature is willing to create it. In other words, nature can, knows what she wishes, and wishes. Now all beings, in a greater or less degree according to their perfection or imperfection, feel this triple condition of being able, knowing, and wishing. Every being can, knows, and wishes, even inorganic matter (here already is the world as will and representation of Schopenhauer), and God is only absolute power, absolute knowledge, and absolute will. This is why all creative things gravitate to God and desire to return to Him as to their origin, and as the perfection of what they are: the universe has nostalgia for God. Campanella was also, as we should say nowadays, a sociologist. He made his "Republic" as Plato had made his. The Republic of Campanella was called the _City of the Sun_. It was a community republic, leavened with aristocracy with "spiritual power" and "temporal power" somewhat after the manner of Auguste Comte. Campanella was a great sower of ideas.