Mechanistic Philosophy of Nature and the Scientific Revolution

1. Mechanistic Philosophy of Nature and the Scientific Revolution

2. Robert Boyle (1627-1691) As in the … clock of Strasbourg, the several pieces making up that curious engine are so framed and adapted, and are put into such a motion, that though the numerous wheels, and other parts of it, move several ways, and that without any thing either of knowledge or design; yet each performs its part in order to the various end, for which it was contrived, as regularly and uniformly as if it knew and were concerned to do its duty. 

3. Johannes Kepler (1571 - 1630) I am much occupied with the investigation of the physical causes. My aim in this is to show that the celestial machine is to be likened not to a divine organism but rather to a clockwork . . . , insofar as nearly all the manifold movements are carried out by means of a single, quite simple magnetic force, as in the case of a clockwork all motions [are caused] by a simple weight. Moreover I show how this physical conception is to be presented through calculation and geometry.

4. We see clocks, artificial fountains, mills and other similar machines that have the power to move themselves in many different ways, although they are made only by humans; and I am sure I could not even imagine as many sorts of movements in this bodily machine as I suppose have actually been made by the hands of God; and however much skill I might attribute to him, you would have reason to believe that his skill was even greater than I had said. . . . Rene Descartes (1596-1650)

5. Greek Atomism as an early Version of the Mechanist Philosophy Leucippus, Democritus, Epicurus All things are composed of eternal, uncreated, invisibly small, indivisible particles, called “atoms”. Atoms move randomly and without purpose in an infinite void, bumping into one another to form macroscopic objects, including living things.

6. Scholastic Arsitotelian Theory of Matter Material Bodies are composed of Primary matter (four elements) which exists only embodied in a quality-bearing Substantialform. The “form” of a thing provides its causal capacities.

7. Scholastic Arsitotelian Theory of Matter Secondary qualities: colors, sounds, odors, tastes, and tactile qualities such as hot and cold. They exist in objects as “real qualities” that are like instances or samples of the quality as experienced. A red thing possesses the quality red in just the same way it possesses a shape: we experience that very redness when we see a red object. The rabbit possesses properties such as the whiteness of its fur: this is a “real quality” of white inhering in each strand of hair.

8. 17th Century Mechanical Theories of Matter Galileo Galilei (1570-1619): Unified theory of inert matter in motion, blindly responding to mathematically formulated, universal laws. Pierre Gassendi (1592-1655): Combined Atomism with Christian Dogma. Rene Descartes (1596-1650): Matter as pure, infinitely divisible, “extension”. Anti-atomist. Robert Boyle (1627-1691): Matter comprises impenetrable atoms. Matter is further divisible in thought or by God, but indivisible as far as natural processes are concerned.

9. 17th Century Mechanical Theories of Matter Galileo Galilei (1570-1619): Unified theory of matter in motion, blindly responding to mathematically formulated, universal physical laws. Pierre Gassendi (1592-1655): Combined Atomism with Christian Dogma. Rene Descartes (1596-1650): Matter as pure, infinitely divisible, “extension”. Anti-atomist. Robert Boyle (1627-1691): Matter comprises impenetrable atoms. Matter is further divisible in thought or by God, but indivisible as far as natural processes are concerned. All against Aristotelian Theories: teleology, differentiated matter, “nature” of matter, primary vs. secondary properties, …

10. 17th Century Mechanical Theories of Matter Galileo Galilei (1570-1619): Unified theory of matter in motion, blindly responding to mathematically formulated, universal physical laws. Pierre Gassendi (1592-1655): Combined Atomism with Christian Dogma. Rene Descartes (1596-1650): Matter as pure, infinitely divisible, “extension”. Anti-atomist. Robert Boyle (1627-1691): Matter comprises impenetrable atoms. Matter is further divisible in thought or by God, but indivisible as far as natural processes are concerned. The mechanical philosophy: “all the phenomena of nature are produced by inert particles of matter in motion.”

11. Boyle’s criticism of the concept of “Nature” When we use “such Phrases, as, that Nature …, or Suction, doth this or that,” we “ascribe to a notional thing, that which, indeed, is perform’dby real Agents; as, when we say, that the Law punishes Murder with Death, that it protects the Innocent, releases a Debtor out of Prison, when he has satisfied his Creditors … That ’tis plain that the Law, which, being in it self a dead Letter, is but a notional Rule, [and] cannot, in a Physical sense, be said to perform these things.” (A Free Enquiry into the Vulgarly Reciev’d Notion of Nature, in The Works of Robert Boyle, vol. 10).

12. Boyle’s theological criticism of the concept of “Nature” “I do not remember, that in the Old Testament, I have met with any one Hebrew word that properly signifies Nature, in the sense we take it in.” Though biblical authors “many times mention the Corporeal Works of God, yet they do not take notice of Nature, which our Philosophers would have his great Vicegerent in what relates to them.” (A Free Enquiry into the Vulgarly Reciev’d Notion of Nature, in The Works of Robert Boyle, vol. 10).

13. Boyle’s theological concept of the clockwork universe “Proponents of the vulgar conception of nature “seem to imagine the World to be after the nature of a Puppet, whose Contrivance indeed may be very Artificial, but yet is such, that almost every particular motion the Artificer is fain … to guide, and oftentimes over-rule, the Actions of the Engine; whereas, according to us, ’tis like a rare Clock, such as may be that at Strasbourg, where all things are so skilfullycontriv’d, that the Engine being once set a Moving, all things proceed according to the Artificers first design, and the Motions of the little Statues, that at such hours perform these or those things, do not require, like those of Puppets, the peculiar interposing of the Artificer, or any Intelligent Agent imployed by him, but perform their functions upon particular occasions, by vertue of the General and Primitive Contrivance of the whole Engine” . (A Free Enquiry into the Vulgarly Reciev’d Notion of Nature, in The Works of Robert Boyle, vol. 10, pp. 464 and 457).

14. Boyle’s atomistic mechanicism • All properties of the material world are reducible to and arise as a consequence of the arrangements and motions of the underlying atoms. • Properties detectable by the senses, (color and taste), and those involved in the interaction of bodies with each other (elasticity and degree of heat), are to be explained in terms of the properties of atoms. • Properties of atoms (shape, size and motion and impenetrability) are the primary properties; more complex properties (secondary) are to be explained in terms of the fundamental laws that govern the motions of atoms.

15. Rene Descartes (1596-1650): Matter as pure, infinitely divisible, “extension”. Anti-atomist. Descartes’ mechanistic philosophy: • Anti-scholastic in its content • Very scholastic in its style • Rationalist - Dualist

16. 1606 JesuitCollège Royal Henry-Le-Grand (La Flèche) 1616: Law at  University of Poitiers1626–1628: Rules for the Direction of the Mind).1630: Le Monde (not published – heard about Galileo)1637: Discours de la méthode (Discourse on the Method).1641: MéditationsMetaphysiques1644: Principia philosophiae. Rene Descartes (1596-1650):

17. Meditation I:Concerning Those Things That Can Be Called into Doubt • “Cogito ergo sum”(Discours de la méthode)

18. “There is nothing in the intellect that was not previously in the senses” Descartes’ criticism of Aristotle’s “Empiricism” … but the senses deceive us … • Human intellect is able to perceive the nature of reality through a purely intellectual perception. In order to procure the fundamental truths of metaphysics, we must “withdraw the mind from the senses.”

19. “Cogito ergo sum” Descartes methodical doubt • “I have convinced myself that there is nothing in the world — no sky, no earth, no minds, no bodies. Doesn't it follow that I don't exist? No, surely I must exist if it's me who is convinced of something. But there is a deceiver, supremely powerful and cunning whose aim is to see that I am always deceived. But surely I exist, if I am deceived. Let him deceive me all he can, he will never make it the case that I am nothing while I think that I am something. Thus having fully weighed every consideration, I must finally conclude that the statement "I am, I exist" must be true whenever I state it or mentally consider it.”

20. “Clear and Distinct Ideas” Descartes methodical doubt WAX: Wax isn't wax because of its color, texture or shape. All of these things can change and the substance still be wax. Wax is perceived "by the intellect alone“. When one understands the mathematical principles of the substance, such as its expansion under heat, figure and motion, the knowledge of the wax can be clear and distinct.

21. “Clear and Distinct Ideas” Descartes methodical doubt If a substance such as wax can be known in this fashion, then the same must be of ourselves. The self is not determined by what we sense of ourselves — these hands, this head, these eyes — but by simply the things one thinks. Thus, one "can't grasp anything more easily or plainly than [his] mind."

22. Clear and distinct ideas: I call a perception clear when it is present and accessible to the attentive mind — just as we see something clearly when it is present to the eye’s gaze and stimulates it with a sufficient degree of strength and accessibility.  I call a perception ‘distinct’ if, as well as being clear, it is so sharply separated from all other perceptions that it contains within it only what is clear.

23. “On the existence of God” Descartes methodical doubt • Something cannot come from nothing. • The cause of an idea must have at least as much formal reality as the idea has objective reality. • I have in me an idea of God. This idea has infinite objective reality. • I cannot be the cause of this idea, since I am not an infinite and perfect being. I don't have enough formal reality. Only an infinite and perfect being could cause such an idea.

24. “On the existence of God” Descartes methodical doubt • So God — a being with infinite formal reality — must exist (and be the source of my idea of God). • An absolutely perfect being is a good, benevolent being. • So God is benevolent... • So God would not deceive me, and would not permit me to err without giving me a way to correct my errors.

25. “On the separation of Mind and Body” Descartes methodical doubt • It is possible for God to create anything I can clearly and distinctly perceive. • If God creates something to be independent of another, they are distinct from each other. • I clearly and distinctly understand my existence as a thinking thing (which does not require the existence of a body). • So God can create a thinking thing independently of a body. • I clearly and distinctly understand my body as an extended thing (which does not require a mind). • So God can create a body independently of a mind. • So my mind is a reality distinct from my body. • So I (a thinking thing) can exist without a body.

26. Metaphysics and Science

27. Metaphysics and Science

28. Metaphysics and Science

29. Metaphysics and Physics

30. Principia Philosophiae The only principles which I accept, or require, in physics are those of geometry and pure mathematics; these principles explain all natural phenomena, and enable us to provide quite certain demonstrations regarding them

31. Principia Philosophiae • I freely acknowledge that I recognize no matter in corporeal things apart from that which the geometers call quantity, and take as the object of their demonstrations, i.e. that to which every kind of division, shape and motion is applicable. Moreover, my consideration of such matter involves absolutely nothing apart from these divisions, shapes and motions; and even with regard to these, I will admit as true only what has been deduced from indubitable common notions so evidently that it is fit to be considered as a mathematical demonstration. And since all natural phenomena can be explained in this way, as will become clear in what follows, I do not think that any other principles are either admissible or desirable in physics.

32. Principia Philosophiae • Thus, extension in length, breadth, and depth, constitutes the nature of corporeal substance; and thought the nature of thinking substance. For every other thing that can be attributed to body, presupposes extension, and is only some mode of an extended thing; as all the properties we discover in the mind are only diverse modes of thinking. Thus, for example, we cannot conceive figure unless in something extended, nor motion unless in extended space, nor imagination, sensation, or will, unless in a thinking thing.

33. Principia Philosophiae • Motion: I have furthermore added that translation takes place 'from the vicinity of contiguous bodies to the vicinity of others', but not 'from one place to another', because, … , the meaning of 'place' is varied and depends on our thinking.

34. Principia Philosophiae • Motion: this translation takes place from the vicinity not of any contiguous bodies, but only 'of those which are viewed as at rest.' For this translation is reciprocal, and body AB cannot be understood to be transferred from the vicinity of body CD unless it is understood at the same time that body CD is also transferred from the vicinity of body AB.

35. Principia Philosophiae • Motion: this translation takes place from the vicinity not of any contiguous bodies, but only 'of those which are viewed as at rest.' For this translation is reciprocal, and body AB cannot be understood to be transferred from the vicinity of body CD unless it is understood at the same time that body CD is also transferred from the vicinity of body AB.

36. Aristotle (Physics): three classes of motion • In place (local motion), • In quantity, or size (growth-diminution), • In quality (alteration)

37. Aristotle’s Motionis the process that a substance goes through in which it loses one “accidental form” and gains another. • Motionis the act of something that does not yet have, but is acquiring, the full act of a new accidental determination, a new quality, size or position.

38. Principia Philosophiae Three laws “of Nature” (of motion) The main argument: “God is the primary cause of motion and always conserves the same quantity of motion in the universe”. God Himself, who in the beginning created matter together with motion and rest, now conserves just as much motion and rest as a whole as He then posited. Now, although this motion in moved matter is nothing other than its mode, nevertheless it has a certain and determinate quantity, which we easily understand to be able to be always the same in the whole universe of things, even though it be changed in its individual parts. So it is evident, as we think, that when one part of matter is moved twice as fast as another, and this second [part of matter] is twice as large as the first, there is as much motion in the smaller as in the larger; and by as much as the motion of one part is made slower, the motion of some other equal to it is made faster.

39. Principia Philosophiae Three laws “of Nature” (of motion) 1. That any object, in and of itself, always perseveres in the same state; and thus what is moved once always continues to be moved. Indeed, from the same immutability of God can be known certain rules or laws of nature, which are the secondary and particular causes of the diverse motions that we perceive in individual bodies. The first of these is that any object, insofar as it is simple and undivided, remains, in and of itself, always in the same state and is never changed, unless by external causes. Thus, if some part of matter is square, we may easily persuade ourselves that it will continue perpetually to be square, unless something should come from elsewhere that changes its shape. If it were at rest, we do not believe it would ever begin to be moved, unless it were impelled to do so by some cause. Nor is there any greater reason, if it were moved, why we should think that it would ever of its own accord, and impeded by nothing else, interrupt its own motion.

40. Principia Philosophiae Three laws “of Nature” (of motion) 1. That any object, in and of itself, always perseveres in the same state; and thus what is moved once always continues to be moved. Certainly, everyday experience of things that are thrown wholly confirms our rule. For there is no other reason why thrown [bodies] should continue in motion for any time after they have been separated from the thrower than that once moved they continue to be moved, until they are slowed by contrary bodies. And it is manifest that they usually are gradually retarded by the air, or some other fluid bodies in which they are moved, and hence their motion cannot last long.

41. Principia Philosophiae Three laws “of Nature” (of motion) 1. That any object, in and of itself, always perseveres in the same state; and thus what is moved once always continues to be moved. We are inclined to posit of all what we seem to have experienced in many, namely that these [motions] by their nature cease, or tend toward rest. Actually, it is wholly in opposition to the laws of nature; for rest is contrary to motion, and nothing can be moved to its contrary, or to its own destruction, by its own nature.

42. Principia Philosophiae Three laws “of Nature” (of motion) 2. That every motion of itself is rectilinear; and hence what is moved circularly tends always to recede from the center of the circle it describes.

43. Principia Philosophiae Three laws “of Nature” (of motion) 3. That  a body, in colliding with another larger one, loses nothing of its motion; but, in colliding with a smaller one, loses as much as it transfers to that one.

44. VortexTheory

45. VortexTheory Imagine, for example, that the points S, E, ε, and A are the centers of which I speak, that all the matter contained in the space FGGF is a heaven turning about the sun marked S, that all the matter of the space HGGH is another heaven turning about the star marked ε, and so on for the others. Thus, there are as many different heavens as there are stars, and, since the number of stars is indefinite, so too is the number of heavens. Thus also the firmament is nothing other than the breadthless surface separating all the heavens from one another..

46. VortexTheory The earth is “at rest” within a vortex band that circled the sun. It does not undergo a change of place relative to the containing surface of the neighboring material particles in its vortex.

47. VortexTheory “The Earth, properly speaking, is not moved, nor are any of the Planets; although they are carried along by the heaven”

50. Magnetism: caused by the circulation of tiny helical particles, "threaded parts", through threaded pores in magnets