_Reader._ Poor Doctor Büchner! You are most unlucky in your allusion to the church. Spiritism is not a priestly invention, nor is it practised under the influence of the priest. The whole world knows that the practice of spiritism is utterly forbidden by the church; and you cannot be ignorant that your insinuation of the contrary is a slander. Perhaps your Masonic conscience allows you to tell lies; but is it wise to do so when the lie is so patent that no one can believe it? _Büchner._ “There can be no doubt that all pretended cases of clairvoyance rest upon fraud or illusion. Clairvoyance—that is, a perception of external objects without the use of the senses—is an impossibility. It is a law of nature which cannot be gainsaid that we require our eyes to see, our ears to hear, and that these senses are limited in their action by space. No one can read an opaque sealed letter, extend his vision to America, see with closed eyes what passes around him, look into the future, or guess the thoughts of others. These truths rest upon natural laws which are irrefutable, and admit, like other natural laws, of no exception. All that we know we know by the medium of our senses. There exist no supersensual and supernatural things and capacities, and they never can exist, as the eternal conformity of the laws of nature would thereby be suspended. As little as a stone can ever fall in any other direction than towards the centre of the earth, so little can a man see without using his eyes” (p. 152). _Reader._ Your reasoning is not sound, doctor. The stone can fall in any direction, if it receives an impetus in that direction; it is only when it is left to itself that it must fall directly towards the centre of the earth. So also a man, when left to himself and his natural powers, cannot see without using his eyes; but if acted on by a preternatural agency, he may be made acquainted with what his eyes cannot see. Your mention of natural laws is uncalled for. You will certainly not pretend that the natural laws, which hold in regard to this visible world, can be assumed to rule the world of the spirits. Moreover, when you say that “there exist no supersensual and supernatural things,” because “the eternal conformity of the laws of nature would thereby be suspended,” you merely make a gratuitous assertion. For as you can raise a weight without suspending the law of gravitation, so can other agents do other things conflicting with the uniform execution of natural laws without the natural laws becoming suspended. Thus your assertion that “there exist no supersensual and supernatural things” is wholly gratuitous, and therefore cannot be the basis of a sound argument against the facts of spiritism. “There is no fighting against facts; it is like kicking against the pricks,” as you say in one of your prefaces (p. xviii.) _Büchner._ “Ghosts and spirits have hitherto only been seen by children, or ignorant and superstitious individuals” (p. 152).