"It would be possible to put a case of a world, in which two straight lines should be universally supposed to include a space. Imagine a man, who had never had any experience of straight lines through the medium of any sense whatever, suddenly placed upon a railway, stretching out on a perfectly straight line to an indefinite distance in each direction. He would see the rails, which would be the first straight lines he ever saw, apparently meeting, or at least tending to meet, at each horizon; and he would thus infer in the absence of all other experience that they actually did enclose a space, when produced far enough. Experience alone could undeceive him. A world in which every object was round with the exception of a straight, inaccessible railway, would be a world in which every one would believe that two straight lines enclosed a space." In his conversation, Mr. Mill expressed his adherence to these humorous sophistries, which have been so keenly criticised by Spencer, and he added, "If we possessed the sense of sight without the sense of touch, we would have no doubt that two or more bodies might exist in the same place, so completely is every so-called _a priori_ axiom dependent on the character of our organs and experiences." IV. Our conversation turned one day on the then existing circumstances in Rome. I compared the religious condition of Rome with that of France; I reminded Stuart Mill of the phenomenon observed by both of us in Paris of the _beau monde_ congregating in a church, and added: "In your Dissertations and Discussions, you have written some words which you will scarcely now defend. You say: 'So far as the upper ranks are concerned, France may as properly be called a Buddhistic as a Catholic country; the latter is not more true than the former.' Would you still maintain this?" He answered: "It was at that time more true than now. In our day a new reaction has taken place, the possibility of which I could not conceive. In my youth I did not believe that man could retrograde; now I know it." A portion of the blame for this retrogression he ascribed to the French university philosophy. He spoke with a deprecation which was not to be wondered at, coming from his lips, of Cousin and his school. "But in spite of all," he concluded, "I cling to my old conviction that the history of France in modern times is the history of all Europe."