The writer next has a group of chapters (vi.-x.) on Man, his composition, relations, and destiny. The chief propositions are in rigorous accord with the general conceptions that have already been set forth. All that man does, and all that passes in him, are effects of the energy that is common to him with the other beings known to us. But, before a true and comprehensive idea of the unity of nature was possible to him, he was so seized by the variety and complication of his organism and its movements that it never came into his mind to realise that they existed in a chain of material necessity, binding him fast to all other forces and modes of being. Men think that they remedy their ignorance of things by inventing words; so they explained the working of matter, in man's case, by associating with matter a hypothetical substance, which is in truth much less intelligible than matter itself. They regarded themselves as double; a compound of matter and something else miraculously united with it, to which they give the name of _mind_ or _soul_, and then they proudly looked on themselves as beings apart from the rest of creation. In plain truth, Mind is only an _occult force_, invented to explain occult qualities and actions, and really explaining nothing. By Mind they mean no more than the unknown cause of phenomena that they cannot explain naturally, just as the Red Indians believed that it was spirits who produced the terrible effects of gunpowder, and just as the ignorant of our own day believe in angels and demons. How can we figure to ourselves a form of being, which, though not matter, still acts on matter, without having points of contact or analogy with it; and on the other hand itself receives the impulsions of matter, through the material organs that warn it of the presence of external objects? How can we conceive the union of body and soul, and how can this material body enclose, bind, constrain, determine a fugitive form of being, that escapes every sense? To resolve these difficulties by calling them mysteries, and to set them down as the effects of the omnipotence of a Being still more inconceivable than the human Soul itself, is merely a confession of absolute ignorance.