The probable increase of the voluntary power of man over his animal frame comes next under Mr Godwin’s consideration, and he concludes by saying, that the voluntary power of some men, in this respect, is found to extend to various articles in which other men are impotent.  But this is reasoning against an almost universal rule from a few exceptions; and these exceptions seem to be rather tricks, than powers that may be exerted to any good purpose.  I have never heard of any man who could regulate his pulse in a fever, and doubt much, if any of the persons here alluded to have made the smallest perceptible progress in the regular correction of the disorders of their frames and the consequent prolongation of their lives.

Mr Godwin says, ’Nothing can be more unphilosophical than to conclude, that, because a certain species of power is beyond the train of our present observation, that it is beyond the limits of the human mind.’  I own my ideas of philosophy are in this respect widely different from Mr Godwin’s.  The only distinction that I see, between a philosophical conjecture, and the assertions of the Prophet Mr Brothers, is, that one is founded upon indications arising from the train of our present observations, and the other has no foundation at all.  I expect that great discoveries are yet to take place in all the branches of human science, particularly in physics; but the moment we leave past experience as the foundation of our conjectures concerning the future, and, still more, if our conjectures absolutely contradict past experience, we are thrown upon a wide field of uncertainty, and any one supposition is then just as good as another.  If a person were to tell me that men would ultimately have eyes and hands behind them as well as before them, I should admit the usefulness of the addition, but should give as a reason for my disbelief of it, that I saw no indications whatever in the past from which I could infer the smallest probability of such a change.  If this be not allowed a valid objection, all conjectures are alike, and all equally philosophical.  I own it appears to me that in the train of our present observations, there are no more genuine indications that man will become immortal upon earth than that he will have four eyes and four hands, or that trees will grow horizontally instead of perpendicularly.

It will be said, perhaps, that many discoveries have already taken place in the world that were totally unforeseen and unexpected.  This I grant to be true; but if a person had predicted these discoveries without being guided by any analogies or indications from past facts, he would deserve the name of seer or prophet, but not of philosopher.  The wonder that some of our modern discoveries would excite in the savage inhabitants of Europe in the times of Theseus and Achilles, proves but little.  Persons almost entirely unacquainted with the powers of a machine cannot be expected to guess at its effects.  I