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reasonable to conclude that motion is the necessary consequence of immutable laws, resulting from the essence, from the properties existing in the different elements, and the various combinations of these elements. Are we not justified, then, in concluding, from these precedents, that there may be an infinity of other combinations, with which we are unacquainted, competent to produce a great variety of motion in matter, without being under the necessity of having recourse, for the explanation, to agents who are more difficult to comprehend than even the effects which are attributed to them?

Had man but paid proper attention to what passed under his review, he would not have sought out of Nature, a power distinguished from herself, to set her in action, and without which he believes she cannot move. If, indeed, by Nature is meant a heap of dead matter, destitute of peculiar qualities purely passive, we must unquestionably seek out of this Nature the principle of her motion. But if by Nature be understood, what it really is, a whole, of which the numerous parts are endowed with various properties, which oblige them to act according to these properties; which are in a perpetual ternateness of action and reaction; which press, which gravitate towards a common center, whilst others depart from and fly off towards the periphery, or circumference; which attract and repel; which by continual approximation and constant collision, produce and decompose all the bodies we behold; then, I say, there is no necessity to have recourse to supernatural powers, to account for the formation of things, and those extraordinary appearances which are the result of motion.