Aristotle, Bacon, Descartes, Boyle
- Aristotle (d. 322 BCE)
1a. On the Parts of Animals, I, i.
[Even a lay-person—someone without an expert’s knowledge of a field—can make a judgment about the method used by the experts.] To give an illustration of what I mean: should we begin by discussing each separate species—man, lion, ox, and the like—taking each kind in hand independently of the rest, or ought we rather to deal first with the attributes which they have in common? Groups that are quite distinct can often manifest many identical phenomena: sleep, for instance, respiration, growth, decay, death, etc. Plainly, [even the lay-person can see that] if we deal with each species independently, we shall frequently be obliged to repeat the same statements over and over again; for horse and dog and man all present every one of the phenomena just listed. We must decide on the right way to proceed.
1b. On the Generation of Animals, III, 10. Aristotle’s terminology has been modified here: he uses ‘leaders’ or ‘kings’ to refer to the ‘queens.’
There is much difficulty about the generation of bees… It is unreasonable to suppose that the workers are female and the drones [are] male, for Nature does not give weapons for fighting to any female, and while the drones are stingless, all the workers have a sting. Nor is the opposite view reasonable, that the workers are male and the drones female, for no males are in the habit of working for their offspring, but as it is the workers do this… It is also impossible that the workers themselves should be some of them male and some female, for in all kinds of animals the two sexes differ. Besides, they would in that case generate their own kind—but no, their brood is not found to come into being if the leaders are not among them. And an argument against both theories, that the young are generated by union of the workers with one another or with the drones, separately or with one another, is this: none of them has ever yet been seen copulating, whereas this would have often happened if the sexes had existed in them.
It remains then, if the workers are generated by copulation at all, that the leaders shall unite to generate them… And, as appears to be the case in certain fishes, the workers generate the drones without copulation, being indeed female in respect of generative power, but containing in themselves both sexes as plants do…
But the leaders also must be generated from something. Since it is neither from the workers nor from the drones, it must be from their own kind. The grubs of the leaders are produced last and are not many in number, so what happens must be this: the leaders generate their own kind but also another kind, that of the workers; the workers again generate another kind, the drones, but do not also generate their own kind, but this has been denied them. And since what is according to Nature is always in due order, therefore it is necessary that it should be denied to the drones even to generate another kind than themselves. This is just what we find happening, for though the drones are themselves generated, they generate nothing else, but the process reaches its limit in the third stage. And so beautifully is this arranged by Nature that the three kinds always continue in existence and none of them fails, though they do not all generate.
It is right also that the leaders, being as it were made with a view to producing young, should remain within, freed from the labor of procuring necessaries, and of a considerable size… And it is right that the drones should be idle as having no weapon to fight for the food and because of the slowness of their bodies. But the workers are intermediate in size between the two other kinds, for this is useful for their work…
Such appears to be the truth about the generation of bees, judging from theory and from what are believed to be the facts about them; the facts, however, have not yet been sufficiently grasped; if ever they are, then credit must be given rather to observation than to theories, and to theories only if what they affirm agrees with the observed facts.
- Francis Bacon (1564-1626): Aphorisms from The Novum Organum.
2a. Aphorisms, Book One
- There are and can exist but two ways of investigating and discovering truth. One hurries on rapidly from the senses and particulars to the most general axioms; from them as principles and their supposed indisputable truth, it derives and discovers the intermediate axioms. This is the way now in use. The other constructs its axioms from the senses and particulars, by ascending continually and gradually, till it finally arrives at the most general axioms, which is the true but untried way.
- Each of these two ways begins from the senses and particulars, and ends in the greatest generalities. But they are immeasurably different; for the one merely touches cursorily the limits of experiment, and particulars, whilst the other runs duly and regularly through them; the one from the very outset lays down some abstract and useless generalities, the other gradually rises to those principles which are really the most common in nature.
- There is no small difference between the idols of the human mind, and the ideas of the divine mind; that is to say, between certain idle dogmas, and the real stamp and impression of created objects, as they are found in nature.
- The idols and false notions which have already preoccupied human understanding, and are deeply rooted in it… will thwart the establishment of the sciences, unless mankind, when forewarned, guard themselves with all possible care against them.
- Four species of idols beset the human mind: to which (for distinction’s sake) we have assigned names: calling the first idols of the tribe; the second idols of the den; the third idols of the market; the fourth idols of the theatre.
- The formation of notions and axioms on the foundation of true induction is the only fitting remedy by which we can ward off and expel these idols…
- The idols of the tribe are inherent in human nature, and the very tribe or race of man. For man’s sense is falsely asserted to be the standard of things. On the contrary, all the perceptions, both of the senses and the mind, bear reference to man, and not to the universe, and the human mind resembles those uneven mirrors, which impart their own properties to different objects, from which rays are emitted, and distort and disfigure them.
- The idols of the den are those of each individual. For everybody has his own individual den or cavern, which intercepts and corrupts the light of nature; either from his own disposition, or from his education, or from his reading, and the authority acquired by those whom he reverences and admires, or from the different impressions produced on the mind…
- There are also idols formed by the reciprocal conversation and society of man with man, which we call idols of the market, from the commerce and association of men with each other. For men converse by means of language; but words are formed at the will of the generality, and they lead to astounding confusion.
- Lastly, there are idols which have crept into men’s minds from the various dogmas of peculiar systems of philosophy, and also from the perverted rules of demonstration, and these we denominate idols of the theatre. For we regard all the systems of philosophy hitherto received or imagined, as so many plays brought out and performed, creating fictitious and theatrical worlds…
- The human understanding, when any preposition has been once laid down, forces everything else to add fresh support and confirmation; it rejects instances that may exist to the contrary, rather than sacrifice the authority of its first conclusions. [Thus the man who was shown temple offerings from those who had survived shipwreck, and was asked to recognize the power of the gods, rightly responded: “But where are the portraits of those who have perished in spite of their vows?”]
- The human understanding resembles not a dry light, but admits a tincture of the will and passions, which generate their own system accordingly: for man always believes more readily that which he prefers. He, therefore, rejects difficulties for want of patience in investigation; sobriety, because it limits his hope; the depths of nature, from superstition; the light of experiment, from arrogance and pride, lest his mind should appear to be occupied with common and varying objects; [and] paradoxes, from a fear of the opinion of the vulgar. In short, his feelings imbue and corrupt his understanding in innumerable and sometimes imperceptible ways.
- But by far the greatest impediment and aberration of the human understanding proceeds from the dullness, incompetence, and errors of the senses… All the better interpretations of nature are worked out by fit and apt experiments, where the senses only judge of the experiment, the experiment judges of nature and the thing itself.
- Some men become attached to particular fancies… They corrupt philosophy and science by their preconceived fancies; of which Aristotle affords us a signal instance, who made his natural philosophy completely subservient to his logic, and thus rendered it little more than useless and disputatious… Gilbert, too, having employed himself most assiduously in the consideration of the magnet, immediately established a system of philosophy to coincide with his favorite pursuit.
- The greatest distinction between different men’s dispositions for philosophy and the sciences is this: some are more vigorous and active in observing the differences of things, others in observing their resemblances. Each of them readily falls into excess…
- Some dispositions evince an unbounded admiration of antiquity, others eagerly embrace novelty. Few can preserve the just medium, so as neither to tear up what the ancients have correctly laid down, nor to despise the just innovations of the moderns…
- The contemplation of nature and of bodies in their individual form distracts and weakens the understanding: but the contemplation of nature and of bodies in their general composition and formation stupefies and relaxes it… These two species of contemplation must therefore be interchanged, and each employed in its turn, in order to render the understanding at once deep and broad…
- Let such, therefore, be our precautions in contemplation, that we may ward off and expel the idols of the den: which mostly owe their birth either to some predominant pursuit; or, secondly, to an excess in synthesis and analysis; or, thirdly, to a party zeal in favor of certain ages; or, fourthly, to the extent or narrowness of the subject. In general, he who contemplates nature should suspect whatever particularly takes and fixes his understanding, and should use so much the more caution to preserve it equable and unprejudiced.
59-60. The idols of the market are the most troublesome of all, those, namely, which have entwined themselves round the understanding from the associations of words and names… Hence the great and solemn disputes of learned men often terminate in controversies about words and names… Take some word for instance, as moist. It will be found that the word moist is nothing but a confused sign of different actions, admitting of no settled and defined uniformity. For it means that which easily diffuses itself over another body; that which is indeterminable and cannot be brought to a consistency; that which yields easily in every direction; that which is easily divided and dispersed; that which is easily united and collected; that which easily flows and is put in motion; that which easily adheres to and wets another body; [and] that which is easily reduced to a liquid state, though previously solid. When, therefore, you come to use this name, in one sense flame is moist, in another air is not moist, in another fine powder is moist, in another glass is moist; …it is quite clear that this notion is hastily abstracted from water only, and common, ordinary liquors, without any due verification of it.
61-62. The idols of the theatre are not innate, nor do they introduce themselves secretly into the understanding; but they are manifestly instilled and cherished by the fictions of theories and depraved rules of demonstration… And they are numerous…
- Aristotle … corrupted natural philosophy by logic… and imposed innumerable arbitrary distinctions upon the nature of things; being everywhere more anxious as to definitions in teaching, and the accuracy of the wording of his propositions, than the internal truth of things… Nor is much stress to be laid on his frequent recourse to experiment in his books on animals, his problems, and other treatises; for he had already decided, without having properly consulted experience as the basis or his decisions and axioms, and after having so decided, he drags experiment along, as a captive constrained to accommodate herself to his decisions; so that he is even more to be blamed than his modern followers (of the scholastic school), who have deserted her altogether.
2b. Aphorisms, Book Two
The investigation of forms proceeds thus: a nature being given, we must first of all have a muster or presentation before the understanding of all known instances which agree in the same nature, though in substances the most unlike. And such collection must be made in the manner of a history, without premature speculation, or any great amount of subtlety. For example, let the investigation be into the form of heat, thus: Instances Agreeing in the Nature of Heat.
- The rays of the sun, especially in summer and at noon.
- The rays of the sun reflected and condensed, as between mountains, or on walls, and most of all in burning glasses and mirrors.
- Fiery meteors.
- Burning thunderbolts.
- Eruptions of flame from the cavities of mountains.
- All flame.
- Ignited solids.
- Natural warm baths.
- Liquids boiling or heated.
- Hot vapors and fumes, and the air itself, which conceives the most powerful and glowing heat if confined, as in reverbatory furnaces.
- Certain seasons that are fine and cloudless by the constitution of the air itself, without regard to the time of year.
- Air confined and underground in some caverns, especially in winter.
- All villous substances, as wool, skins of animals, and down of birds, have heat.
- All bodies, whether solid or liquid, whether dense or rare (as the air itself is), held for a time near the fire.
- Sparks struck from flint and steel by strong percussion.
- All bodies rubbed violently, as stone, wood, cloth, etc., insomuch that poles and axles of wheels sometimes catch fire; and the way they kindled fire in the West Indies was by attrition.
- Green and moist vegetables confined and bruised together, as roses packed in baskets; insomuch that hay, if damp, when stacked, often catches fire.
- Quicklime sprinkled with water.
- Iron, when first dissolved by strong waters in glass, and that without being put near the fire. And in like manner tin, etc., but not with equal intensity.
- Animals, especially and at all times internally; though in insects the heat is not perceptible to the touch by reason of the smallness of their size.
- Horse dung and like excrements of animals, when fresh.
- Strong oil of sulphur and of vitriol has the effect of heat in burning linen.
- Oil of marjoram and similar oils have the effect of heat in burning the bones of the teeth.
- Strong and well rectified spirit of wine has the effect of heat, insomuch that the white of an egg being put into it hardens and whitens almost as if it were boiled, and bread thrown in becomes dry and crusted like toast.
- Aromatic and hot herbs…, although not warm to the hand (either whole or in powder), yet to the tongue and palate, being a little masticated, they feel hot and burning.
- Strong vinegar, and all acids, on all parts of the body where there is no epidermis, as the eye, tongue, or on any part when wounded and laid bare of the skin, produce a pain but little differing from that which is created by heat.
- Even keen and intense cold produces a kind of sensation of burning…
- Other instances.
- René Descartes (1596-1650)
3a. The Discourse on the Method of Proceeding Rightly in the Sciences.
… The power of judging aright and of distinguishing truth from error, which is properly what is called good sense or reason, is by nature equal in all men… The diversity of our opinions, consequently, does not arise from some being granted with a larger share of reason than others, but solely from this, that we conduct our thoughts along different ways, and do not fix our attention on the same objects. For to be possessed of a vigorous mind is not enough; the prime requisite is rightly to apply it…
My present purpose, then, is not to teach the method which each ought to follow for the right conduct of his reason, but solely to describe the way in which I have endeavored to conduct my own. … I hope it will prove useful to some without being hurtful to any, and that my openness will find some favor with all.
From my childhood, I eagerly desired instruction. But as soon as I had finished the entire course of study, I found myself involved in so many doubts and errors, that I was convinced I had advanced no farther in all my attempts at learning, than the discovery at every turn of my own ignorance. And yet I was studying in one of the most famous schools in Europe…
… For these reasons, as soon as my age permitted me to pass from under the control of my instructors, I entirely abandoned the study of letters, and resolved no longer to seek any other science than the knowledge of myself, or of the great book of the world. I spent the remainder of my youth in traveling, in visiting courts and armies, in holding conversation with men of different dispositions and ranks, in collecting varied experiences, in testing myself in the different situations into which fortune threw me, and, above all, in making such reflection on the matter of my experience as guarantee my improvement. For it occurred to me that I should find much more truth in the reasonings of each individual with reference to the affairs in which he is personally interested, and the outcome of which must soon punish him if he has judged amiss, than in those conducted by a man of letters in his study, regarding theoretical matters that are of no practical moment, and followed by no consequences to himself… In addition, I had always a most earnest desire to know how to distinguish the true from the false, in order that I might be able clearly to distinguish the right path in life, and proceed in it with confidence.
…I found [in the world] scarce any ground for settled conviction … [so that I learned not to accept as true those things] of which I had been persuaded merely by example and custom; and thus I gradually disentangled myself from many errors powerful enough to darken our natural intelligence, and weaken us in great measure from listening to reason. But after I had been occupied several years in thus studying the book of the world, and in essaying to gather some experience, at length I resolved to make myself an object of study, and to employ all the powers of my mind in choosing the paths I ought to follow, an undertaking which was accompanied with greater success than it would have been had I never left my country or my books…
3b. Rules for the Direction of the Mind.
RULE I. The aim of our studies must be the direction of our mind so that it may form solid and true judgments on whatever matters arise.
RULE II. We must occupy ourselves only with those objects that our intellectual powers appear competent to know certainly and indubitably.
RULE III. As regards any subject we propose to investigate, we must inquire not what other people have thought, or what we ourselves conjecture, but what we can clearly and manifestly perceive by intuition or deduce with certainty. There is no other way of acquiring knowledge.
Rule III lists all the intellectual activities by means of which we can attain to knowledge of things without any fear of deception; it allows of only two such: intuition and deduction. By intuition I mean, not the wavering assurance of the senses, or the deceitful judgment of the imagination, but a conception, formed by unclouded mental attention, so easy and distinct as to leave no room for doubt in regard to the thing we are understanding. It comes to the same thing if we say: It is an indubitable conception formed by an unclouded intellect; one that originates solely from the light of reason, and is more certain even than deduction, because it is simpler… Thus, anybody can see by mental intuition that he himself exists, that he thinks, that a triangle is bounded by just three lines, and a globe by a single surface, and so on; there are far more of such truths than most people observe, because they disdain to turn their mind to such easy topics… The self-evidence and certainty of intuition is, moreover, necessary [for deductive reasoning].
… By deduction… I mean any necessary conclusion from other things known with certainty. … Many things are known although not self-evident, so long as they are deduced from principles known to be true by a continuous and uninterrupted movement of thought, with clear intuition of each point. [Similarly,] we know the last link of a long chain is connected with the first, even though we do not view in a single glance all the intermediate links on which the connection depends; we need only to have gone through the links in succession and to remember that from the first to the last each is joined to the next. Thus we distinguish… between intuition and certain deduction: the latter, unlike the former, is conceived as involving a movement or succession; it is unlike intuition in not requiring something evident at the moment, but rather, so to say, borrowing its certainty from memory. From this we may gather that when propositions are direct conclusions from first principles, we may say that they are known by intuition or by deduction, according to different ways of looking at them; but first principles themselves can be known only by intuition, and remote conclusions, on the other hand, only by deduction.
These are the two most certain ways to knowledge; and on the side of the mind no more must be admitted; all others must be rejected as suspect and liable to mislead. This, however, does not prevent our believing that divine revelation is more certain than any knowledge; for our faith in it, so far as it concerns obscure matters, is an act not of the mind but of the will; and any intellectual foundations that it may have can and must be sought chiefly by one or other of the two ways I have mentioned…
3c. René Descartes, cont’d., and modern commentator: Edward Slovik, Cartesian Cosmology and Astrophysics, with selections from Descartes’ Principia Philosophiae (Principles of Philosophy), 1644. Descartes rejected all possibility of a void. He proposed instead a completely full universe: a plenum (as opposed to a vacuum), and he argued that the planets moved in a kind of whirlpool of tiny particles that circled around the sun. This was his vortex (or whirlpool) theory. It eliminated the need for occult natures and motions.
…In essence, Descartes’ vortex theory attempts to explain celestial phenomena, especially the orbits of the planets or the motions of comets, by situating them (usually at rest) in these large circling bands. The entire Cartesian plenum is comprised of a network or series of separate, interlocking vortices. In our solar system, for example, the matter within the vortex has formed itself into a set of stratified bands, each lodging a planet, that circle the sun at varying speeds…
On the whole, the vortex theory offered the natural philosopher a highly intuitive model of celestial phenomena that was compatible with the mechanical philosophy. The theory was regarded as superior to Newton’s theory of universal gravitation since it did not posit a mysterious, occult quality (gravity) as the cause of the planetary orbits or the free-fall of terrestrial objects. The vortex theory likewise provided a built-in explanation for the common direction of all planetary orbits. Additionally, the vortex theory allowed Descartes to endorse a form of Copernicanism without running afoul of Church censorship. Since the alleged motion of the earth was one of the Church’s principal objections to Galileo’s science, Descartes hoped to avoid this objection by placing the earth at rest within a vortex band that circled the sun, such that the earth does not undergo a change of place relative to the containing surface of the neighboring material particles in its vortex band (Pr. III, 24-31; sec. 3). Through this ingenious maneuver, Descartes could then claim that the earth does not move—via his definition of place and motion—and yet maintain the Copernican hypothesis that the earth orbits the sun. “The Earth, properly speaking, is not moved, nor are any of the Planets; although they are carried along by the heaven” (Pr. III, 28).
[What is the material stuff that carries the planets around in the vortex? It is particulate matter, either] atom-sized, globules (secondary matter) or the “indefinitely” small debris (primary matter) left over from the impact and fracture of the larger elements. Tertiary matter, in contrast, comprises the large, macroscopic material elements (Pr. III, 48-54). These three kinds of matter plus the three laws of nature are responsible for all cosmological phenomena in Descartes’ system, including gravity….
Selection from Descartes’s Principia Philosophiae.
21-23. Matter is extension. The idea of extension that we conceive in any space whatever is exactly the same as the idea of material substance in that same space. Since all matter is identified as such solely by the fact that it is extended, the matter of the heaven does not differ from that of that earth… The universe of material substance has no limits to its extension. Wherever we imagine those limits to be, we are always able to imagine spaces beyond them…
23-25. All variation in matter depends on movement—and by movement, I mean only local movement: the transference of one part of matter or of one body, from the vicinity of those bodies immediately contiguous to it and considered as at rest, into the vicinity of some others… Movement and rest are but diverse modes of the body in which they are found; they are not substances. So, too, shape is a mode of the thing shaped….
26-28. Our body normally moves as a result of a conscious effort of our will, while it remains at rest by the sole fact of being attached to the earth by weight, a force that we do not feel—but we err to think that more action is required for movement than for rest. We correct this false prejudice by noting that effort is required not only to move external bodies, but also to stop them… Movement, properly understood, concerns only the bodies contiguous to the body which is moving…
- Each individual body has only one movement peculiar to it, since it is understood to move away from only a certain number of bodies contiguous to it and which are considered at rest. A body may also participate in countless other movements, since it is a part of other bodies which have movements. Consider a sailor wearing a watch while he is on a ship: the wheels of his watch have a single movement peculiar to them [relative to the immediately contiguous watch-case], but they will also participate in the movement of the ship tossing on the sea…
- God is the primary cause of motion, and He always maintains an equal quantity of it in the universe.
- First law of nature: that each thing, as far as is in its power, always remains in the same state, and that, consequently, when it is once moved, it always continues to move…Hence a thrown body moves until it is slowed down by other bodies…
- Second law of nature: all movement is, of itself, in straight lines; consequently, bodies moving in a circle always tend to move away from the center of the circle which they are describing…
- Third law of nature: a body, upon coming in contact with a stronger one, loses none of its motion; but upon coming in contact with a weaker one, loses as much as it transfers to that weaker body… We know from experience that when any hard moving bodies strike an unyielding body, they do not cease moving, but rather are driven back in the opposite direction. On the other hand, when they strike a yielding body to which they can easily transfer all their motion, they immediately come to rest…
End of selection from Descartes’s Principia Philosophiae.
Back to Slowik.
As for the creation of [Descartes’s] vortex system: …God partitioned the plenum into equal-sized portions, and then placed bodies into various circular motions that, ultimately, formed the three elements of matter and the vortex systems.
…In the long run, Descartes’ vortex theory failed for two fundamental reasons: first, neither Descartes nor his followers ever developed a systematic mathematical treatment of the vortex theory that could match the accuracy and predictive scope of the (continuously improving) Newtonian theory; and second, many attempts by Cartesian natural philosophers to test Descartes’ various ideas on the dynamics of circularly moving particles (e.g., by using large spinning barrels filled with small particles) did not meet the predictions advanced in the Principles.
- Robert Boyle (1627-1691): Tracts Containing New Experiments. In this brief excerpt, Boyle’s language has not been edited.
A Way of Kindling Brimstone in [an air pump], unsuccessfully tried. We took a small earthen melting Pot, of an almost Cylindrical figure, and well glaz’d (when it was first bak’d) by the heat; and into this we put a small cylinder of Iron of about an inch in thickness, and half as much more in Diameter, made red hot in the fire; and having hastily pump’d out the Air, to prevent the breaking of the Glass; when this vessel seem’d to be well emptied, we let down, by a turning key, a piece of Paper, wherein was put a convenient quantity of flower of Brimstone, under which the iron had been carefully plac’d; so that, being let down, that vehement heat did, as we expected, presently destroy the contiguous paper; whence the included Sulphur fell immediately upon the iron, whose upper part was a little concave, that it might contain the flowers when melted. But all the heat of the iron, though it made the Paper and Sulphur smoke, would not actually kindle either of them that we could perceive.
 Aristotle (384bce-322bce): Greek philosopher and naturalist, student of Plato and , briefly, teacher of Alexander of Macedon (later, Alexander the Great). http://classics.mit.edu/Aristotle/parts_animals.1.i.html
 Descartes, René (1596-1650): French philosopher, mathematician, and scientist; his most lasting contribution is probably the Cartesian coordinate system. His physical theory of vortices, according to which the heavenly bodies were caught in a material whirlpool, remained popular in France long after the publication of Newton’s law of universal gravitation.
edu/archives/fall2005/entries/descartes-physics/> René Descartes, Principia Philosophiae, trans. V.R. Miller and R. P. Miller (London: D.Reidel, 1983), 49-61. Additional editing by LG.
 Boyle, Robert (1627-1691): Anglo-Irish physicist and chemist, and author of The Sceptical Chymist. With the help of Robert Hooke and Denis Papin, he researched the properties of air and pioneered the air pump (i.e., the vacuum pump). http://web.lemoyne.edu/~giunta/boyle.html