sooner imagined a spirit within himself, than giving it extent, he made it universal; then ascribed to it all those causes with which his ignorance prevents him from becoming acquainted, thus he identified himself with the Author of Nature--then availed himself of the supposition to explain the connection of the soul with the body: his self-complacency prevented his perceiving that he was only enlarging the circle of his errors, by pretending to understand that which it is more than possible he will never be permitted to know; his self-love prevented him from feeling, that whenever he punished another for not thinking as he did, that he committed the greatest injustice, unless he was satisfactorily able to prove that other wrong, and himself right: that if he himself was obliged to have recourse to hypothesis--to gratuitous suppositions, whereon to found his doctrine, that from the very fallibility of his nature, these might be erroneous: thus GALLILEO was persecuted, because the metaphysicians, the theologians of his day, chose to make others believe what it was evident they did not themselves understand. As soon as I feel an impulse, or experience motion, I am under the necessity to acknowledge extent, solidity, density, impenetrability in the substance I see move, or from which I receive impulse: thus, when action is attributed to any cause whatever, I am obliged to consider it MATERIAL. I may be ignorant of its individual nature, of its mode of action, or of its generic properties; but I cannot deceive myself in general properties, which are common to all matter: this ignorance will only be increased, when I shall take that for granted of a being, of which from that moment I am precluded by what I admit from forming any idea, which moreover deprives it completely either of the faculty of moving itself, giving an impulse, or acting. Thus, according to the received idea of the term, a spiritual substance that moves itself, that gives motion to matter, and that acts, implies a contradiction, that necessarily infers a total impossibility.