Authors/Thomas Aquinas/physics/L8/lect5

Lecture 5 Five ways in which things may be disposed with respect to motion or rest. Two first excluded

Latin	English
	Lecture 5 Five ways in which things may be disposed with respect to motion or rest. Two first excluded.
lib. 8 l. 5 n. 1 Postquam philosophus in septimo ostenderat quod in moventibus et in mobilibus non est procedere in infinitum, sed est devenire ad aliquod primum; et hic iam ostendit quod motus semper fuit et semper erit; ulterius procedit ad inquirendum conditionem primi motus et primi motoris. Et dividitur in partes duas: in prima ostendit quod primus motus est sempiternus, et quod primum movens est omnino immobile; secundo ex hoc procedit ad ostendendum qualis sit primus motus, et qualis sit primus motor, ibi: at vero aliud facientibus principium et cetera. Prima autem pars dividitur in partes tres: in prima ponit sub quaestione quandam divisionem quinquemembrem; in secunda excludit tres partes propositae divisionis, ibi: omnia igitur quiescere etc.; tertio inquirit de duobus residuis membris, quod eorum sit verius, quia ex hoc dependet veritas quam inquirere intendit, ibi: omnia autem velle aliquando quidem et cetera.	1004. Having shown in Book VII that there is not an infinite process in movers and in mobiles but that a first must be reached, and having now shown that motion has always been and always will be, the Philosopher goes on further to consider the condition of the first motion and of the first mover. And his treatment is divided into two parts. In the first he shows that the first motion is eternal and that the first mover is entirely immobile; Secondly, from this he proceeds to show the condition of the first motion and of the first mover, (L. 14). The first is divided into three parts: In the first he gives a division having five members; In the second he excludes three members of this division, at 1006; Thirdly, he investigates the two remaining members to see which of them is truer, because the truth of what he intends to settle depends on it, (L. 6).
lib. 8 l. 5 n. 2 Dicit ergo primo quod principium sequentis considerationis, qua inquirere intendimus de primo motu et primo motore, est quod pertinet ad dubitationem praedictam (quam scilicet movit solvendo secundam rationem): unde contingit quod quaedam aliquando moventur, et aliquando quiescunt iterum, et non semper vel moventur vel quiescunt, ex quo ponitur motus sempiternus in communi? Et dicit quod necesse est dispositionem rerum, quantum ad motum vel quietem, tripliciter se habere. Quorum unus modus est, ut omnia semper quiescant, et nihil aliquando moveatur; secundus modus est, ut omnia semper moveantur, et nihil quiescat; tertius modus est, quod quaedam moveantur et quaedam quiescant. Sed iste tertius modus iterum dividitur in tres modos. Quorum primus est, quod quaedam moveantur et quaedam quiescant, ita tamen quod ea quae moventur, semper moveantur, et ea quae quiescunt, semper quiescant, et nihil sit quod quandoque moveatur et quandoque quiescat. Secundus modus est e contrario, quod omnia sunt nata et moveri et quiescere, et nihil est quod semper moveatur vel semper quiescat. Tertius modus huius secundae divisionis est, quod alia semper sint immobilia et nunquam moveantur; alia semper mobilia et nunquam quiescant; alia vero possint accipi cum utroque, scilicet cum motu et quiete, ita quod quandoque moveantur et quandoque quiescant. Et istud ultimum membrum est nobis determinandum pro veritate, quia in hoc habentur solutiones omnium obiectorum. Et quando hoc ostenderimus, habebimus finem quem intendimus in isto opere, scilicet pervenire ad primum motum sempiternum, et ad primum movens immobile. Sic ergo tertium membrum primae divisionis dividitur in tria membra, et fiunt in universo quinque membra huius divisionis. Est autem considerandum quod in tribus horum membrorum omnia entia ponuntur unius dispositionis; sicut patet in primo membro, quo dicitur omnia semper quiescere; et in secundo, quo dicitur omnia semper moveri; et in quarto, quo dicitur omnia quandoque quiescere et quandoque moveri. In uno autem membro, scilicet in tertio, dividuntur entia in duas dispositiones, scilicet quod quaedam semper moveantur, et quaedam semper quiescant. In uno etiam membro, scilicet in quinto, dividuntur entia in tres dispositiones, scilicet quod quaedam semper moveantur, quaedam nunquam moveantur, quaedam quandoque moveantur et quandoque non moveantur. Et considerandum est quod in hoc ultimo membro non facit mentionem de quiete, sed de immobilitate: quia primus motor, qui nunquam movetur, non potest dici proprie quiescere; quia, ut in quinto dictum est, illud proprie quiescit, quod natum est moveri et non movetur.	1005. He says therefore First (773 253 a22) that the reason for the following consideration, in which we intend to investigate about the first motion and the first mover, is that it pertains to a question he raised in answering the second argument (given in the preceding lecture), namely, that of whence it happens that certain things are at one time in motion and at another time at rest, and are not either always in motion or always at rest since motion in common is considered perpetual. And he says that the ways in which things are disposed with respect to motion or rest are necessarily limited to three. The first of which is that all things be always at rest and nothing ever in motion; the second is that all things be always in motion and nothing at rest; the third way is that some things are in motion and others at rest. But the third way is again divided into three ways. The first of these is that some things are in motion and some at rest in the sense that the ones in motion are always in motion and those at rest always at rest, and nothing is at one time in motion and at another time at rest. The second way is the converse, i.e., that all things are apt to be in motion and to rest and that nothing is either always in motion or always at rest. The third way is that certain things are always immobile and never in motion; others are always mobile and never at rest; still others may be taken with both, i.e., with motion and rest, so as to be in motion at one time and at rest at another. This last member must be determined by us to be the truth, because in it are contained the solutions of all objections. And when we shall have shown this, we shall possess the end which we intend in this work, namely, to arrive at a first eternal motion and a first immobile mover. Therefore, it is in the above manner that the third member of the first division is divided into three members, thus making a general division consisting of five members. Now, it should be noticed that in three of these members all things are respectively put in one definite disposition; for example, in the first member all things are taken to be always at rest; in the second all things are always in motion; and in the fourth all things alternate between motion and rest. But in one member, namely, the third, beings are divided according to two dispositions, so that some are always in motion and others always at rest. Finally, in one member, the fifth, beings are divided according to three dispositions; namely, some are never in motion, others are never at rest, while the others are sometimes in motion and sometimes not. Notice, too, in this last member that it is not rest but immobility that is posited; because the first mover, who is never moved, can not strictly be said to be at rest, for, as was said in Book V, only what is apt to be moved, and is not being moved, is properly said to be at rest.
lib. 8 l. 5 n. 3 Deinde cum dicit: omnia igitur quiescere etc., excludit tria membra praedictae divisionis. Et primo ponit quod non omnia quiescunt semper; secundo quod non omnia moventur semper, ibi: fere autem adhuc etc.; tertio excludit tertium membrum, quo dicebatur quod quae moventur, moventur semper, et quae quiescunt, quiescunt semper, ibi: at vero neque alia quidem et cetera. Circa primum tria ponit. Quorum primum est, quod ex quadam intellectus infirmitate procedit, quod aliqui dicant omnia quiescere, et quod inquirant ad hoc aliquam sophisticam rationem, dimisso sensu: procedit enim ex hoc quod intellectus non est sufficiens ad dissolvendum sophisticas rationes, quae repugnant iis quae sunt manifesta secundum sensum. Dictum est autem in I topicorum, quod non est curandum disputare contra quascumque positiones vel problemata, de quibus aliquis dubitat indigens sensu vel poena: unde contra istam positionem non oportet dubitare, propter stultitiam dicentis. Secundum quod dicit est, quod ista dubitatio non est de aliquo particulari ente, sed universaliter de toto ente. Neque etiam pertinet solum ad naturalem philosophum, sed quodammodo pertinet ad omnes scientias demonstrativas, et ad omnes opiniones, idest ad omnes artes quae utuntur quibusdam opinionibus, sicut rhetorica et dialectica: quia omnes artes et scientiae utuntur motu; practicae quidem, quasi dirigentes aliquos motus, naturalis autem philosophia, speculando naturam motus et mobilium. Mathematici etiam utuntur motu imaginato, dicentes quod punctus motus facit lineam. Metaphysicus autem considerat de primis principiis. Sic igitur patet, quod destruere motum repugnat omnibus scientiis. Error autem qui pertinet ad omnia entia et ad omnes scientias, non est reprobandus a naturali, sed a metaphysico. Non ergo pertinet ad naturalem contra istum errorem disputare. Tertium quod dicit est, quod irrationabiles et importunae dubitationes de principiis in doctrinis mathematicis, non pertinent ad mathematicum, ut eas removeat; et similiter est in aliis scientiis. Et similiter nec ad physicum pertinet destruere huiusmodi positionem, quae repugnat suis principiis. In qualibet enim scientia supponitur pro principio definitio subiecti: unde et in scientia quae est de natura, supponitur quasi principium, quod natura sit principium motus. Sic ergo per tria media apparet quod ad naturalem non pertinet contra hanc positionem disputare.	1006. Then at (774 253 a32) he excludes three members of the division. First he posits that not all things are always at rest; Secondly, that not all things are always in motion, at 1007; Thirdly, he excludes the third member, in which it was said that the things in motion are always in motion and those at rest are always at rest, (L. 6). In regard to the first he posits three statements. The first of these is that it is due to a weakness of understanding that some affirm rest of all things and in support of their stand search for a sophistic reason without referring to sense. For it proceeds on the fact that the intellect is not capable of destroying sophistical arguments which conflict with things evident to sense. But it has been said in Topics I that there is no need to dispute against positions or problems that are in a mind which needs sense or punishment. Hence it is not necessary to dispute this position, due to its stupidity. The second thing he says is that this problem does not concern a particular being but being in general. Nor does it affect natural science alone, but in a way all demonstrative sciences and all opinions, i.e., all the arts which use opinions, as do rhetoric and dialectics, for all the arts and sciences make use of motion. For the practical arts in a way direct certain motions, and natural philosophy speculates about the nature of motion and about mobile beings. Mathematicians, too, make use of motion, i.e., of an imagined one, saying that a point in motion makes a line. The metaphysician, however, considers first principles. Accordingly, it is plain that to destroy motion conflicts with all sciences. Now an error that affects all beings and all sciences is not to be reproved by the philosopher of nature but by the metaphysician. Therefore, it is not the business of natural philosophy to dispute this error. The third thing he says is that unreasonable and inappropriate problems about the principles of mathematical sciences do not pertain to mathematics to be answered. The same is true in the other sciences. In like manner, it is not the business of the physicist to destroy an affirmation that is contrary to its principles. For in each science the definition of the subject is assumed as a principle; hence in the science which deals with nature, it is assumed as a principle that nature is a principle of motion. Accordingly, in the light of these three statements, it is apparent that it does not belong to natural philosophy to dispute this position.
lib. 8 l. 5 n. 4 Deinde cum dicit: fere autem etc., excludit secundum membrum, quo ponebatur ab Heraclito omnia semper moveri. Et primo comparat hanc opinionem praecedenti opinioni, quae ponebat omnia semper quiescere: et dicit quod dicere omnia moveri semper, ut Heraclitus dixit, est quidem falsum et contra principia scientiae naturalis; sed tamen minus repugnat arti haec positio quam prima. Et quod quidem repugnet arti manifestum est: quia tollit suppositionem scientiae naturalis, in qua ponitur quod natura non solum est principium motus, sed etiam quietis; et sic patet quod similiter naturale est quies, sicut et motus. Unde sicut prima opinio, quae destruebat motum, erat contra scientiam naturalem; ita et haec positio quae destruit quietem. Ideo autem dixit hanc opinionem esse minus praeter artem, quia quies nihil est aliud quam privatio motus: quod autem non sit privatio motus, magis potest latere quam quod non sit motus. Sunt enim quidam motus parvi et debiles, qui vix possunt sentiri: et sic potest videri quod aliquid quiescat, quod non quiescit. Sed motus magni et fortes latere non possunt: unde non potest dici quod decipiatur sensus in perceptione motus, sicut in perceptione quietis. Et ideo secundo, ibi: et dicunt quidam etc., ostendit quomodo hanc secundam positionem aliqui posuerunt. Et dicit quod quidam, scilicet Heraclitus et eius sequaces, dixerunt quod omnia quae sunt, semper moventur, non solum quaedam, aut aliquando; sed motus latet sensum nostrum. Qui si loquerentur de aliquibus motibus, eorum dictum sustineri posset: sunt enim aliqui motus qui nos latent. Sed quia non determinant de quali motu loquantur, sed dicunt de omnibus motibus, ideo non est difficile contra illos obiicere; quia multi motus sunt, de quibus manifestum est quod non possunt semper esse.	1007. Then at (775 253 b6) he excludes the second member, in which Heraclitus posited that all things are always being moved. And first he compares this opinion with the previous one which posited that all things are always at rest; and he says that to say that all things are always in motion, as Heraclitus said, is both false and contrary to the principles of natural science. Yet this position is not in as great conflict with the art as the first one is. But that it does conflict with the art is clear, because it takes away the assumption of natural science that nature is principle not only of motion but also of rest, which supposition makes it clear that rest is something natural just as motion is. Hence, just as the first opinions which destroyed motion, was against natural science, so too is this one that destroys rest. The reason why he says that this opinion is less against art is that rest is nothing more than the privation of motion. But it is less evident that there is no motion than that there is no privation of motion. For there are some motions so weak and insignificant that they can be scarcely noticed; for that reason it is easy to suppose that something is at rest when it really is not. But great and strong motions cannot be concealed; hence it cannot be said that the senses are deceived in perceiving motion as they are in perceiving rest. Therefore, Secondly, at (776 253 b9) he shows how some posited this second opinion. And he says that some, such as Heraclitus and his supporters, have said that all things which exist are always in motion, and not some things only or just at some time, but this motion eludes our senses. Now, if they say this of some motions, they are correct; for some motions do elude us. But because they do not qualify their statement but speak of all motions, it is not hard to find arguments against them, for there are many motions which evidently could not have existed always.
lib. 8 l. 5 n. 5 Tertio ibi: neque enim augeri etc., ponit rationes contra opinionem praedictam. Et primo quantum ad motum augmenti; secundo quantum ad motum alterationis, ibi: similiter autem et in alteratione et cetera. Tertio quantum ad motum localem, ibi: et secundum quod fertur. Ideo autem ab augmento incipit, quia Heraclitus maxime inducebatur ad suam positionem ex consideratione augmenti. Videbat enim aliquem augeri secundum aliquam modicam quantitatem in uno anno; et supponens augmentum esse continuum, credebat quod in qualibet parte illius temporis secundum aliquid illius quantitatis augeretur, et tamen non sentitur istud augmentum, quia fit in modica temporis parte; et sic arbitrabatur esse in aliis quae videntur quiescere. Dicit ergo contra hoc Aristoteles, quod non est possibile continue aliquid augeri vel minui, ita scilicet quod quantitas aucta dividatur secundum tempus, ita quod in qualibet parte aliquid eius augeatur: sed interponitur medium tempus post augmentum unius partis, in quo nihil augetur, sed fit dispositio ad augmentum sequentis partis. Et hoc manifestat per similia. Quorum primum est, quia videmus quod gutta pluviae multiplicata conterit lapidem. Secundum exemplum est, quia videmus quod nascentia, idest plantae in lapidibus nascentes, lapides dividunt. Nec possumus dicere quod si gutta multiplicata tantum fodit vel removet de lapide in tanto tempore, quod medietas guttarum prius in medio tempore removerit medietatem illius quantitatis; sed ita contingit hic, sicut in trahentibus navem. Non enim si centum homines trahunt navem per tantum spatium in tanto tempore, sequitur quod media pars illorum moveat per medietatem spatii in eodem tempore, vel per idem spatium in duplo tempore, ut in septimo dictum est. Ita etiam non sequitur, si multae guttae effodiunt lapidem, quod aliqua pars illarum guttarum prius removerit medietatem in aliquo tempore. Et huius ratio est, quia illud quod removetur a lapide per multas guttas, est quidem divisibile in plura; sed tamen non seorsum aliquid illorum plurium a lapide removetur, sed simul omnes partes, prout sunt in potentia in toto remoto. Et loquitur hic de primo quod removetur: nihil enim prohibet per longinquum tempus aliquam tam magnam quantitatem removeri a lapide per guttas, quod aliqua pars remota est prius per partem guttarum: est tamen devenire ad aliquod quantum remotum, quod totum simul removetur, et non pars post partem. In remotione ergo illius totius, nulla guttarum praecedentium aliquid removebat, sed disponebat tantum ad remotionem: ultima autem agit in virtute omnium, removendo id ad cuius remotionem ceterae disponebant. Et similiter etiam est in motu diminutionis. Non est enim necessarium quod si aliquid decrescit tantum in tanto tempore, licet illa quantitas in infinitum dividatur, quod semper in qualibet parte temporis aliquid illius quantitatis subtractum abeat; sed totum simul aliquando abibit. Et similiter etiam est in augmento. Et sic non oportet quod continue aliquid augeatur vel minuatur.	1008. Thirdly, at (777 253 b13) he forms the arguments against this position. First with respect to the motion of growth; Secondly, with respect to the motion of alteration, at 1009; Thirdly, with respect to local motion, at 1012. The reason he begins with growth is that Heraclitus was led to his doctrine as a result of considering growth. For he observed that a person grows a small amount in one year and, supposing that growth is continuous, he believed that in each part of that year he was increased with respect to part of that quantity; and yet that increase is not sensed, because it comes in a small portion of time, He reasoned, therefore, that the same thing happens in other things which seem to be at rest. Against this Aristotle says that it is not possible for a thing to be continually increased or diminished so that the increased quantity can be divided according to time in such a way that in each part of time there is a corresponding increase. Rather, there is, after the increase of one part, a time in which there is no increase but a disposition is produced for the increase of the next part. And this he explains with kindred examples. The first of these is that we see that the multiplication of drops of rain breaks a stone. The second example is that we see that things being born, i.e., that plants born in stones divide the stones. Now, we cannot say that, if the repeated drops dig out or remove a certain quantity of the stone in a given time, half of this number of drops in half the time would previously remove half of that quantity. But what happens here is what happens with regard to shiphaulers. For it does not follow, if 100 men pull a ship a certain distance in a given time, that fifty of them will move it half the distance in the same time or the full distance in twice the time—this was said in Book VII. So also it does not follow, if many drops cave in a stone, that some part of those drops had previously removed the half in some certain time. The reason for this is that what is removed from the stone by many drops is indeed divisible into many parts, but none of them is removed separately from the stone, for all the parts are removed at once, in the sense that they are in the totality removed in potency. And he is speaking here of the first total quantity that is removed, for there is nothing to prevent that, over a long period of time, such a large quantity, be removed from the stone by these drops that a certain part may have been removed previously by a part of these drops. But we must come to a removed quantity which is removed all together and not part after part. Therefore, in the removing of that whole, none of the preceding drops removed anything, but merely disposed for its removal. However, the last acts in virtue of all and removes what the others had disposed to be removed. The same is true in the motion called decrease. For it is not necessary, if something decreases a certain amount in a given time (even though the quantity be divided ad infinitum), that in every part of that time a corresponding part of the removed quantity should depart; rather, at some time a given amount will depart all together. The same holds in increase. Consequently, it is not required that something be continuously increased or decreased.
lib. 8 l. 5 n. 6 Deinde cum dicit: similiter autem et in alteratione etc., contradicit praedictae positioni quantum ad alterationem; et hoc tribus rationibus. Primo enim dicit quod similiter dicendum est in qualibet alteratione, sicut dictum est in augmento. Quamvis enim corpus quod alteratur, sit partibile in infinitum, non tamen oportet quod propter hoc alteratio in infinitum dividatur, ita scilicet quod in qualibet parte temporis aliquid alterationis fiat; sed multoties fit velox alteratio, ita scilicet quod multae partes corporis alterati simul alterantur, sicut accidit in densatione sive congelatione aquae. Tota enim aliqua aqua simul congelatur, non pars post partem (si tamen accipiatur multum de aqua, nihil prohibet partem post partem congelari). Est autem considerandum, quod hoc quod hic dicitur de alteratione et augmento, videtur contrariari iis quae dicta sunt in sexto, ubi ostensum est quod motus dividitur secundum divisionem temporis et mobilis et rei secundum quam est motus. Sed sciendum est quod Aristoteles in sexto determinabat de motu in communi, non applicando ad aliqua mobilia; et ideo ea quae ibi de motu tractavit, accipienda sunt secundum exigentiam continuitatis motus: hic autem loquitur de motu, applicando ad determinata mobilia, in quibus contingit aliquem motum interrumpi et non continuari, qui secundum rationem communem motus posset esse continuus.	1009. Then at (778 253 b23) he contradicts the above-mentioned position of continuous motion with respect to alteration, and this with three arguments. First, he says that what was said about increase, applies also to alteration. For although a body that is being altered is infinitely divisible, that is no reason for supposing that alteration is divided ad infinitum, so that for each period of time a part of the alteration should occur. Rather, alteration very often takes place swiftly, i.e., many parts of the altered body are altered all at once, as happens when water is condensed or congealed. For a whole mass of water is congealed all at once and not part after part (although if it be a large mass of water, there is nothing to prevent part congealing after part). It should be noticed that what Aristotle says here about alteration growth seems contrary to what was said in Book VI, where it was shown that motion is divided according to the division of the time, and of the mobile, and of the sphere of motion. But it should be recognized that in Book VI Aristotle was talking about motion in common, without application to definite mobiles. Therefore, what he discussed there must be taken according to the requirements of motion’s continuity; but at present he is speaking of motion with application to definite mobiles, in which a motion can be interrupted and not be continuous, which, when viewed under the common aspect, could be continuous.
lib. 8 l. 5 n. 7 Secundam rationem ponit ibi: amplius cum infirmetur aliquis et cetera. Et dicit quod si aliquis qui infirmatur, debeat sanari, necesse est quod sanetur in aliquo tempore, et non in termino temporis. Et necesse est ulterius quod ipsa mutatio sanationis tendat in determinatum terminum, scilicet in sanitatem, et in nihil aliud. Sic ergo omnis alteratio requirit determinatum tempus et determinatum terminum (quia omnis alteratio est in contrarium, ut in quinto dictum est): nulla autem talis mutatio est semper continua: dicere ergo quod aliquid semper et continue alteretur, est dubitare de manifestis.	1010. He gives the second argument at (779 253 b26), and he says that if a sick person is to get well, he has to become healed in a period of time and not in a terminus (an instant?) of the time. And it is further necessary that the very change, which is healing, tend to a definite terminus, i.e., to health and not to anything else. Accordingly, every alteration requires a definite time and a definite terminus, because every alteration tends to a contrary, as was said in Book V. But no such change is always continuous. Therefore, to say that something is being always and continuously altered, is to speak against the facts.
lib. 8 l. 5 n. 8 Tertiam rationem ponit ibi: atque lapis et cetera. Et dicit quod lapis non fit neque durior neque mollior, etiam per temporis longinquitatem: et sic stultum est dicere quod omnia semper alterentur.	1011. The third argument he gives at (780 253 b30) and he says that a stone does not become harder or softer, even after a very great period of time; thus it is foolish to say that all things are always being altered.
lib. 8 l. 5 n. 9 Deinde cum dicit: et secundum quod fertur etc., contradicit praedictae opinioni quantum ad motum localem, dupliciter. Primo quidem, quia aliqui motus locales et quietes ita sunt manifesti, quod latere non possunt: mirabile enim videtur si lateat quando lapis fertur deorsum, aut quando quiescit in terra. Et sic non potest dici quod propter latentiam motus localis ponantur omnia semper moveri localiter.	1012. Then at (781 253 b31) he contradicts the opinion at issue with respect to local motion, on two counts. First, indeed, because some local motions and rests are so evident that they cannot be hidden. For it would be strange if it were hidden from us when a stone is carried downwards or when it is at rest on the earth. Consequently, it cannot be said that, because of the concealment of local motions, all things should be supposed to be always being moved locally.
lib. 8 l. 5 n. 10 Secundo ibi: amplius autem terra etc., ratiocinatur sic. Terra et quodlibet aliud corpus naturale, quando sunt in propriis locis, ex necessitate naturae quiescunt, et non removentur ex propriis locis, nisi per violentiam: sed manifestum est quaedam corporum naturalium esse in propriis locis: necesse est ergo dicere quod quaedam quiescant secundum locum, et quod non omnia localiter moveantur. Ultimo autem epilogando concludit, quod ex praemissis et aliis similibus potest aliquis scire, quod impossibile est aut semper omnia moveri, sicut dixit Heraclitus, aut semper omnia quiescere, sicut dixit Zeno et Parmenides et Melissus.	1013. Secondly, at (782 253 b33) he argues thus: Earth and any other natural body, when they are in their due places, rest from a necessity of nature and are not removed except by force. But it is evident that certain natural bodies are in their due place. Therefore, it is necessary to say that some things are at rest with respect to place and that not all things are being moved locally. Finally, he concludes in summary that, from the foregoing and other things similar to the foregoing, anyone can know that it is impossible for all things always to be in motion, as Heraclitus said, or for all things always to be at rest, as Zeno and Parmenides and Melissus said,