hence, when c is at rest, there will be in it an impressed force impelling it upward, which will be 4.</s>
<s id="id.1.2.6.10.11">But if it is abandoned by the impressing force, it will recede with an impressed force of 4: hence after such a retreat it will not be moved upward; but it will go down very slowly at the beginning, and afterwards it will be moved more swiftly, according as the contrary force will be weakened. </s>
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<s id="id.1.2.6.11.00"/>
<s id="id.1.2.6.11.01">We assert without doubt that this is the true, proper, and most important cause by which natural motion at the beginning is slower; no doubt those who will examine it properly and fairly will embrace it and will follow it as very true. </s>
<s id="id.1.2.6.11.02">But could these same things be obtained by an easier method? </s>
<s id="id.1.2.6.11.03">Indeed they could, and they are easily known to one proceeding from natural considerations: for, pray, do not the two following propositions coincide: "Forced motion is slow at the end", "Therefore natural motion is slow at the beginning"? </s>
<s id="id.1.2.6.11.04">For natural motion follows violent motion, and the end of violent motion is linked with the beginning of the natural: but the cause of the slowness of violent motion at the end is the small excess by which the impelling force exceeds the resisting heaviness, that is, by which the cause of violent motion exceeds the cause of natural motion: hence, in the same way, one must deem that the cause of the slowness of natural motion at the beginning is the small excess by which the cause of natural motion surpasses the cause of violent motion, i.e. by which the heaviness which exerts pressure downward exceeds the lightness, that is the impressed force, impelling upward. </s>
<s id="id.1.2.6.11.05"> You can therefore see how well true things suit one another. </s>
<s id="id.1.2.6.11.06">Now from this way of considering things anyone will easily be able to understand how these two motions are not truly contraries, but rather a certain motion composed of the violent and the natural {1}: for these local motions somehow depend on certain other alterative motions, so long as the proper heaviness and the extrinsic lightness (for we will hereafter call the impressed force {2} lightness) are mixed in the mobile. </s>
<s id="id.1.2.6.11.07">From such a mixture it follows, and in a sense by accident, that a mobile is moved sometimes upward sometimes downward: for when in the mixture there is more lightness than heaviness, from it an effect of lightness, namely an upward motion, will arise; but if in the mobile, lightness having been diminished, there is more heaviness, an effect of heaviness, namely a downward motion, will emanate. </s>
<s id="id.1.2.6.11.08">But this alterative motion, while the mobile is moved from lightness to heaviness, is a single and continuous motion: as when hot water by accident becomes cold, it is moved with a single motion towards cold, and its motion from hot to tepid is not something else than its motion from tepid to cold: thus, when from light something becomes neither heavy nor light, the motion is not separate from the motion during which from neither heavy nor light it becomes heavy. </s>
