Book,  Paragraph

  1   I,  2 |          say, is their principle of movement. But all movement that is
  2   I,  2 |      principle of movement. But all movement that is in place, all locomotion,
  3   I,  2 |            three dimensions, so its movement completes itself in three
  4   I,  2 |        which possess a principle of movement in their own nature, such
  5   I,  2 |           is such a thing as simple movement, and that circular movement
  6   I,  2 |         movement, and that circular movement is an instance of it, and
  7   I,  2 |       instance of it, and that both movement of a simple body is simple
  8   I,  2 |           body is simple and simple movement is of a simple body (for
  9   I,  2 |           simple body (for if it is movement of a compound it will be
 10   I,  2 |          own nature with a circular movement. By constraint, of course,
 11   I,  2 |          since there is one sort of movement natural to each of the simple
 12   I,  2 |             Again, if the unnatural movement is the contrary of the natural
 13   I,  2 |           will follow that circular movement, being a simple motion,
 14   I,  2 |            then (1) the body, whose movement is circular, is fire or
 15   I,  2 |             And so, since the prior movement belongs to the body which
 16   I,  2 |       naturally prior, and circular movement is prior to straight, and
 17   I,  2 |           is prior to straight, and movement in a straight line belongs
 18   I,  2 |            it follows that circular movement also must be the movement
 19   I,  2 |           movement also must be the movement of some simple body. For
 20   I,  2 |           some simple body. For the movement of composite bodies is,
 21   I,  2 |             We may take it that all movement is either natural or unnatural,
 22   I,  2 |             unnatural, and that the movement which is unnatural to one
 23   I,  2 |   necessarily follows that circular movement, being unnatural to these
 24   I,  2 |        these bodies, is the natural movement of some other. Further,
 25   I,  2 |           on the one hand, circular movement is natural to something,
 26   I,  2 |              on the other hand, the movement of the rotating bodies about
 27   I,  2 |             inconceivable that this movement alone should be continuous
 28   I,  2 |         body so moved is fire, this movement is just as unnatural to
 29   I,  2 |         unnatural to it as downward movement; for any one can see that
 30   I,  3 |            or away from the centre. Movement in a straight line certainly
 31   I,  3 |        naturally, since one sort of movement is, as we saw, appropriate
 32   I,  3 |             Suppose, then, that the movement is unnatural. In that case,
 33   I,  3 |         case, if it is the downward movement which is unnatural, the
 34   I,  3 |            is unnatural, the upward movement will be natural; and if
 35   I,  3 |           it. But since the natural movement of the whole and of its
 36   I,  3 |      unalterable. For alteration is movement in respect of quality; and
 37   I,  4 |          applies also the circular, movement from A to B being opposed
 38   I,  4 |        being opposed as contrary to movement from B to A. But what is
 39   I,  4 |           the opposition is between movement from C to D and from D to
 40   I,  4 |         strength, there would be no movement either way, and if one of
 41   I,  4 |          not be moving with its own movement, would be useless, in the
 42   I,  5 |         something to which circular movement belongs.~(2) Again, if from
 43   I,  5 |             a beginning also of the movement, and consequently also of
 44   I,  5 |            upon C as centre. In its movement it will cut BB continuously
 45   I,  5 |          above in the discussion of movement.) And it makes no difference
 46   I,  5 |             has only to imagine the movement to be slow where both move
 47   I,  5 |             since the very smallest movement conceivable must take an
 48   I,  5 |            there can be no circular movement, and similarly where there
 49   I,  5 |            there can be no infinite movement; and from this it follows
 50   I,  6 |            it is indeterminate, the movement within it will be infinite;
 51   I,  6 |           half as long over a given movement. Further, a finite weight
 52   I,  6 |            say that the time of the movement can be continually diminished,
 53   I,  7 |  necessarily also finite, since the movement of a simple body is simple,
 54   I,  7 |             upward, can prolong its movement to infinity. For it is true
 55   I,  7 |        there is no other (straight) movement beyond those mentioned:
 56   I,  7 |      secondly, could the body whose movement is circular be infinite,
 57   I,  7 |       finite, C the time of a given movement produced by one in the other.
 58   I,  7 |       caused to undergo any sort of movement whatever, by in the time
 59   I,  7 |         greater and less. If so, no movement can be caused in the infinite
 60   I,  7 |             agent will produce that movement in a less patient in an
 61   I,  7 |          can the infinite produce a movement in the finite in any time
 62   I,  7 |            infinite can effect this movement. And, as to infinite time,
 63   I,  7 |             less quantity makes the movement in a less time. Let E then,
 64   I,  7 |             upon by A, complete the movement in the time D. Then, as
 65   I,  7 |            time has no end, but the movement communicated has.~If therefore
 66   I,  7 |             the goal of its natural movement and another, equally great,
 67   I,  7 |           the goal of its unnatural movement. Moreover, whether its rectilinear
 68   I,  7 |             whether its rectilinear movement is natural or constrained,
 69   I,  7 |          given in our discussion of movement, where it is shown that
 70   I,  7 |             must necessarily be one movement of all the multitude. They
 71   I,  7 |            motion; and without that movement is impossible. A thing must
 72   I,  8 |     constraint. Further, if a given movement is due to constraint, its
 73   I,  8 |             to the centre here, its movement from here to there will
 74   I,  8 |             without constraint, its movement hither will be natural.
 75   I,  8 |            natural. And the natural movement in each case is one. Further,
 76   I,  8 |           the bodies must have some movement, since the fact that they
 77   I,  8 |           body which has no natural movement at all cannot be moved by
 78   I,  8 |           the bodies have a natural movement, the movement of the particular
 79   I,  8 |             a natural movement, the movement of the particular instances
 80   I,  8 | consideration of the other kinds of movement also makes it plain that
 81   I,  8 |             the goal of the natural movement must differ in form-just
 82   I,  8 |          differ in form-just as the movement of coming to health does
 83   I,  8 |         will be the limits of their movement. (Even in circular movement
 84   I,  8 |         movement. (Even in circular movement there is a sort of opposition
 85   I,  8 |            the diameter, though the movement as a whole has no contrary:
 86   I,  8 |      contrary: so that here too the movement has in a sense an opposed
 87   I,  8 |          This conclusion that local movement is not continued to infinity
 88   I,  8 |             the upper place. But if movement were infinite speed would
 89   I,  8 |          superior speed in downward movement implies superior weight,
 90   I,  8 |           be the upward or downward movement; but the fact is the reverse:
 91   I,  8 |           the quicker always is its movement towards its own place. Again,
 92   I,  8 |             Again, the speed of the movement would not increase towards
 93   I,  8 |        extrusion; for a constrained movement always diminishes in speed
 94   I,  8 |          the nature of the circular movement, which must be eternal both
 95   I,  9 |           and time is the number of movement. But in the absence of natural
 96   I,  9 |            natural body there is no movement, and outside the heaven,
 97   I,  9 |          excellences. Its unceasing movement, then, is also reasonable,
 98  II,  1 |        divine thing which possesses movement, but movement such as has
 99  II,  1 |             possesses movement, but movement such as has no limit and
100  II,  1 |       itself the limit of all other movement. A limit is a thing which
101  II,  1 |         from moving with some other movement more natural to itself.
102  II,  1 |          itself. Such a constrained movement would necessarily involve
103  II,  1 |           whirled round, received a movement quick enough to overpower
104  II,  1 |    painlessly or happily, since the movement involves constraint, being
105  II,  2 |         part, in a thing capable of movement, from which movement first
106  II,  2 |             of movement, from which movement first begins. Growth starts
107  II,  2 |        animate, have a principle of movement within themselves. For in
108  II,  2 |           observe a part from which movement originates. Some do not
109  II,  2 |            is the region from which movement originates, right the region
110  II,  2 |             possess, a principle of movement, and that the heaven is
111  II,  2 |            possesses a principle of movement, clearly the heaven must
112  II,  2 |             of the beginning of its movement. For even if it never began
113  II,  2 |             is the pole we see, the movement will be leftward, which
114  II,  2 |          For the principle of their movement has the reverse position,
115  II,  2 |         reverse position, since the movement itself is the contrary of
116  II,  3 |         eternal life. Therefore the movement of that which is divine
117  II,  3 |          only if the body’s natural movement were towards the centre.
118  II,  3 |            centre. But the circular movement is natural, since otherwise
119  II,  3 |          privation of lightness and movement. But further, if fire and
120  II,  3 |           should be eternal, if its movement cannot be regarded as naturally
121  II,  3 |           bodies we know to possess movement. Thus we see that generation
122  II,  3 |       circular motion: for a single movement of the whole heaven would
123  II,  3 |            required because eternal movement in one body necessitates
124  II,  4 |            revolves with a circular movement must be spherical. The same
125  II,  4 |            minimum, and the minimum movement is the swiftest, then, clearly,
126  II,  4 |        swiftest, then, clearly, the movement of the heaven must be the
127  II,  4 |           is the shortest; and that movement is the swiftest which follows
128  II,  5 |       possible, and, just as upward movement is the superior form of
129  II,  5 |        superior form of rectilinear movement, since the upper region
130  II,  5 |          than the lower, so forward movement is superior to backward,
131  II,  5 |           it is best to move with a movement simple and unceasing, and,
132  II,  6 |          have next to show that the movement of the heaven is regular
133  II,  6 |          first heaven and the first movement; for the lower spheres exhibit
134  II,  6 |          movements into one. If the movement is uneven, clearly there
135  II,  6 |       between the two. But circular movement, having no beginning or
136  II,  6 |        without a break. If then its movement has no maximum, it can have
137  II,  6 |        cause of the irregularity of movement must lie either in the mover
138  II,  6 |          might well be an irregular movement in the moved. But none of
139  II,  6 |             be change either in the movement as a whole, from fast to
140  II,  6 |            again is a change in the movement as a whole admissible. Retardation
141  II,  6 |            the capacity. But if the movement is retarded it must necessarily
142  II,  6 |     perpetual retardation. For such movement would be infinite and indefinite,
143  II,  6 |           and indefinite, but every movement, in our view, proceeds from
144  II,  6 |       heaven could not complete its movement. For, as a given walk or
145  II,  6 |              one might suppose, the movement of the heaven could not
146  II,  6 |      alternative is to say that the movement exhibits an alternation
147  II,  6 |       eternal, and further that its movement is regular, has now been
148  II,  7 |            an element whose natural movement is circular. In so saying
149  II,  7 |            the air by their motion. Movement tends to create fire in
150  II,  7 |         agitation produced by their movement, the upper bodies are carried
151  II,  8 |        circle has completed its own movement, i.e. traversed its own
152  II,  8 |          same should be true of the movement of the stars contained in
153  II,  8 |          this would show that their movement was not their own, but due
154  II,  8 |       greater circle with a swifter movement of the star contained in
155  II,  8 |            first place, the quicker movement of the larger circle is
156  II,  8 |            that if the stars have a movement of their own, it will be
157  II,  8 |             all to exhibit the same movement: but the only star which
158  II,  8 |             appears to possess this movement is the sun, at sunrise or
159  II,  8 |           produces an appearance of movement in the star: for it makes
160  II,  8 |         makes no difference whether movement is set up in the ray or
161  II,  8 |          seen. Therefore, since any movement of their own which the stars
162  II,  8 |             themselves, and no such movement is observed in them, clearly
163  II,  8 |          them, clearly they have no movement of their own.~There is,
164  II,  8 |           organ appropriate to such movement. For nature leaves nothing
165  II,  8 |         things which have organs of movement. This is just why it seems
166  II,  8 |             the most convenient for movement in one place, making possible,
167  II,  8 |   selfcontained motion, for forward movement it is the most unsuitable,
168  II,  8 |          shape which best suits the movement of the one and the immobility
169  II,  9 |            that the theory that the movement of the stars produces a
170  II,  9 |             in size and in speed of movement has that effect. Also, when
171  II,  9 |         given forth by the circular movement of the stars is a harmony.
172  II,  9 |           like might be said of the movement of the vessel itself. But
173  II,  9 |           the result, that if their movement were other than it is, nothing
174  II,  10|             the heavens is a simple movement and the swiftest of all,
175  II,  10|       swiftest of all, and that the movement of all other bodies is composite
176  II,  11|             things which possess no movement a shape particularly unadapted
177  II,  11|           particularly unadapted to movement. Such a shape is the sphere,
178  II,  11|          possesses no instrument of movement. Clearly then their mass
179  II,  12|        successive body a variety of movement proportionate to its distance
180  II,  12|           immediately with a single movement, and the bodies intermediate
181  II,  12|           cost of a multiplicity of movement.~As to the difficulty that
182  II,  12|        actually a body; so that its movement will be a joint product.
183  II,  12|        motion, to which the general movement is, as it were, added. But
184  II,  12|             of substance and shape, movement and order, have now been
185  II,  13|         different ways in which the movement or rest of the earth has
186  II,  13|           in midair, should show no movement at all. Yet here is this
187  II,  13|          will continue its downward movement with nothing to stop it.
188  II,  13|             with those who speak of movement in this way cannot be confined
189  II,  13|       whether bodies have a natural movement or not, whether there is
190  II,  13|        natural but only constrained movement. Seeing, however, that we
191  II,  13|          say, which have no natural movement, have no constrained movement;
192  II,  13|       movement, have no constrained movement; and where there is no natural
193  II,  13|          natural and no constrained movement there will be no movement
194  II,  13|           movement there will be no movement at all. This is a conclusion,
195  II,  13|     inconceivable, since rest, like movement, is either natural or constrained.
196  II,  13|             if there is any natural movement, constraint will not be
197  II,  13|            the so-called "whirling" movement by which its parts came
198  II,  13|            a higher speed, prevents movement of the earth, as the water
199  II,  13|            moving with the downward movement which is natural to it.)
200  II,  13|             earth move to then? Its movement to the centre was constrained,
201  II,  13|             does not prevent upward movement, then no more could air
202  II,  13|           below it prevent downward movement. For the same cause must
203  II,  13|            that, while the whirling movement may have been responsible
204  II,  13|          and the light. Rather that movement caused the pre-existent
205  II,  13|          apply to any body, whereas movement to the centre is peculiar
206  II,  13|          case that a thing to which movement this way and that is equally
207  II,  13|        shape, position, and rest or movement of the earth.~
208  II,  14|            motion. It cannot be the movement of the earth itself. If
209  II,  14|       portion of it would have this movement; but in fact every part
210  II,  14|      constrained and unnatural, the movement could not be eternal. But
211  II,  14|             moves with the circular movement, except the first sphere,
212  II,  14|         earth.~Further, the natural movement of the earth, part and whole
213  II,  14|          earth is the goal of their movement is indicated by the fact
214  II,  14|           single thing has a single movement, and a simple thing a simple:
215  II,  14|       belong to the same thing, and movement away from the centre is
216  II,  14|           centre is the contrary of movement to it. If then no portion
217  II,  14|           the manner of its rest or movement, our discussion may here
218  II,  14|         they attribute the downward movement to constraint, and it is
219  II,  14|          endowed with a centripetal movement. When the mixture, then,
220  II,  14|          hand, there were a similar movement from each quarter of the
221  II,  14|        would be the natural form of movement towards what is naturally
222 III,  1 |        power in themselves to cause movement, and also their alterations
223 III,  1 |           generation or any kind of movement, but if so they belong to
224 III,  1 |     considered in our discussion of movement, where we have shown that
225 III,  2 |        bodies should have a natural movement may be shown as follows.
226 III,  2 |          and if they have no proper movement they must move by constraint:
227 III,  2 |         unnatural. Now an unnatural movement presupposes a natural movement
228 III,  2 |      movement presupposes a natural movement which it contravenes, and
229 III,  2 |     constrained in a place to which movement was constrained, natural
230 III,  2 |     constrained, natural in a place movement to which was natural. Now
231 III,  2 |    impossible. The hindrance to its movement, then, we will suppose,
232 III,  2 |       natural rest proves a natural movement to the place of rest. Hence
233 III,  2 |             bodies are in perpetual movement in the void or infinite,
234 III,  2 |        their motion and the kind of movement which is natural to them.
235 III,  2 |           must still have a natural movement which the constrained contravenes,
236 III,  2 |           ultimate natural cause of movement and each preceding term
237 III,  2 |          moved without order. Their movement must have been due either
238 III,  2 |          their nature. And if their movement was natural, a moment's
239 III,  2 |           virtue of its own natural movement, and the other bodies, moving
240 III,  2 |            that bodies in unordered movement should combine in some cases
241 III,  2 |            is that, if the cause of movement is single, they must move
242 III,  2 |         kind, have a common goal of movement. Again, disorderly movement
243 III,  2 |         movement. Again, disorderly movement means in reality unnatural
244 III,  2 |          means in reality unnatural movement, since the order proper
245 III,  2 |          notion that the disorderly movement is infinitely continued.
246 III,  2 |         bodies are separated and in movement. Hence Empedocles begins
247 III,  2 |          every body has its natural movement, which is not constrained
248 III,  2 |            continue its constrained movement infinitely. For there will
249 III,  2 |           nature" means a source of movement within the thing itself,
250 III,  2 |        while a force is a source of movement in something other than
251 III,  2 |         itself qua other, and since movement is always due either to
252 III,  2 |            nature or to constraint, movement which is natural, as downward
253 III,  2 |             is natural, as downward movement is to a stone, will be merely
254 III,  2 |           force, while an unnatural movement will be due to the force
255 III,  2 |             the force transmits the movement to the body by first, as
256 III,  2 |          this function, constrained movement would be impossible. And
257 III,  2 |         impossible. And the natural movement of a body may be helped
258 III,  2 |        heavy, and (2) how unnatural movement takes place.~From what has
259 III,  3 |          natural body has it proper movement, and movements are either
260 III,  4 |          our discussion of time and movement. They are also bound to
261 III,  4 |        every element has its proper movement, and a simple body has a
262 III,  4 |            simple body has a simple movement, and the number of simple
263 III,  5 |         they allow only one natural movement, which is the same for every
264 III,  5 |            possesses a principle of movement. If then all bodies are
265 III,  5 |          are one, all will have one movement. With this motion the greater
266 III,  6 |            if it has no tendency to movement, it will be an immovable
267 III,  8 |         first place, with regard to movement both are in error. These
268 III,  8 |             figures best adapted to movement; they are not, however,
269 III,  8 |        however, well adapted to the movement of fire, which is an upward
270 III,  8 |           an upward and rectilinear movement, but rather to that form
271 III,  8 |            to that form of circular movement which we call rolling. Earth,
272  IV,  1 |        proper part of the theory of movement, since we call things heavy
273  IV,  1 |            nature is concerned with movement, and these things have in
274  IV,  1 |          some spark (as it were) of movement, all inquirers avail themselves
275  IV,  1 |            the centre I call upward movement and that which is towards
276  IV,  1 |          towards it I call downward movement. (The view, urged by some,
277  IV,  1 |             of its natural downward movement.~
278  IV,  2 |          and the quicker its upward movement: and, similarly, in the
279  IV,  2 |           similarly, in the reverse movement from above downward, the
280  IV,  2 |             to void, but the upward movement of the greater is quicker
281  IV,  2 |          less, just as the downward movement of a mass of gold or lead,
282  IV,  2 |           in attributing the upward movement of bodies to a void which
283  IV,  2 |        therefore each causes a like movement in other things, there was
284  IV,  2 |            what is the cause of its movement? Not, surely, its voidness:
285  IV,  3 |      connected with them. The local movement of each body into its own
286  IV,  3 |             in fact, three kinds of movement, affecting respectively
287  IV,  3 |        produces upward and downward movement is that which produces weight
288  IV,  3 |             heavy or light, and the movement of each body to its own
289  IV,  3 |             the natural goal of the movement of each single part is also
290  IV,  3 |       response to a slight external movement reach health or increase,
291  IV,  3 |             of the several kinds of movement; in order of being then
292  IV,  3 |          stays the healing. But the movement is also due to the original
293  IV,  4 |          quantity is increased, the movement is the same, though swifter.
294  IV,  4 |             ways. First, because no movement can continue to infinity.
295  IV,  4 |             come-to-be than be, and movement is a coming to-be in one
296  IV,  4 |           Secondly, like the upward movement of fire, the downward movement
297  IV,  4 |      movement of fire, the downward movement of earth and all heavy things
298  IV,  4 |             the region in which the movement of these bodies takes place.
299  IV,  5 |           drawn up, when the upward movement of air which has had a common
300  IV,  5 |            little air in the upward movement and air excel water in the
301  IV,  5 |         excel water in the downward movement, as we have already often
302  IV,  6 |        drive" (meaning by drive the movement of the upward moving bodies)