Last post I excerpted selections of E.A. Burtt's Metaphysical Foundations of Modern Science on Newton as a metaphysician (in the pejorative sense). In this post I have collected other scintillating selections from the book, and grouped them into a few categories. The divisions are somewhat artificial, because the categories are interrelated, and some passages could arguable appear in more than one category.
On Qualities and the Mind
The moderns, starting with Descartes, distinguished primary from secondary qualities. (Though as far back as Peter Ramus, there was a movement to sever the mind from the real contact with the world we call knowledge.) Primary qualities are predominantly geometrical, while secondary qualities are those that, to put it briefly, give the world its vibrancy, such as colors, tones, tastes, smell, textures. Here are some selections on qualities, quantities and the modern project of divorcing the mind from the natural world of qualities, and draining life from the universe. (The two longer ones are real gems.)
[Kepler:] "Wherever there are qualities, there are likewise quantities, but not always vice versa." (67)
[Galileo:] "Now this tickling is all in us, and not in the feather, and if the animate and sensitive body be removed, it is nothing more than a mere name. Of precisely a similar and not greater existence do I believe these various qualities to be possessed, which are attributed to natural bodies, such as tastes, odours, colours, and others." (86)
Why, now, are we sure that the primary, geometrical qualities inhere in objects as they really are, while the secondary qualities do not? How is it that "all other things we conceive to be compounded out of figure, extension, motion, etc., which we cognize so clearly and distinctly that they cannot be analysed by the mind into others more distinctly known?" Descartes' own justification for this claim is that these qualities are more permanent than the others. In the case of the piece of wax, which he used for illustrative purposes in the second Mediation, no qualities remained constant but those of extension, flexibility, and mobility, which as he observes, is a a fact perceived by the understanding, not by the sense or imagination. Now flexibility is not a property of all bodies, hence extension and mobility alone are left as the constant qualities of all bodies as such; they can by no means be done away with while the bodies remain. But, we might ask, are not colour and resistance equally constant properties of bodies? Objects change in colour, to be sure, and there are varying degrees of resistance, but does one meet bodies totally without colour or resistance? the fact is and this is of central importance for our whole study, Descartes' real criterion is not permanence but the possibility of mathematical handling; in his case, as with Galileo, the whole course of his thought from his adolescent studies on had inured him to the notion that we know objects only in mathematical terms, and the sole type for him of clear and distinct ideas had come to be mathematical ideas, with the addition of certain logical propositions into which he had been led by the need of a firmer metaphysical basis for his achievements, such as the proposition that we exist, that we think, etc. Hence the secondary qualities, when considered as belonging to objects, like the primary, inevitably appear to his mind obscure and confused; they are not a clear field for mathematical operations. (117-118)
All the non-geometrical properties are to be shorn from the res extensa and located in the mind. (122)
Now Hobbes recognizes that he has obligated himself to give an explanatory account, in terms of bodies and motion, of these images [that make up reasoning], inasmuch as they do not obviously present themselves as either bodies, or motions, or located in the brain. This explanation, which appears first in the Treatise of [sic] Human Nature, is of profound significance in the early development of the new doctrine of the human mind, and represents Hobbes' chief importance in the current which leads on to the metaphysics of Newton. (129)
[Isaac Barrow holds that] the attempt to speak of the mathematician as dealing with an ideal or intelligible realm as opposed to the realm of sensible objects is mistaken: it is the sensible realm, so far as it is intelligible, especially as it reveals quantitative continuity, that is the object of all science. Thus physics, so far as it is a science, is wholly mathematical, likewise all of mathematics is applied in physics, hence we may say that the two sciences are co-extensive and equal. (151-2)
Descartes, bold metaphysician that he was, had answer ready as regards space—he seized upon it as the very substance of the material universe, crowding into the immaterial world of thought whatever could not be fully treated geometrically. (160)
[Boyle's general solution to the problem of secondary qualities:] it is that in objects themselves these secondary qualities exist as "a disposition of its constituent corpuscles, that in case it were truly applied to the sensory of an animal there would be no such thing as pain, yet a pin may, upon the account of its figure, be fitted to cause pain in case it were moved against a man's finger..." Inasmuch, however, as there are men and animals in the world, such a "disposition" or "fitness" in things is just as real as the qualities it possesses in itself. (182)
[Descartes sought to avoid] attributing to either ethereal matter or other bodies any qualities not deducible from extension. As we have observed, the mere fact that the ether assumes and maintains the vortical form implies in it qualities that go far beyond extension... (192)
The world of physics is the sensible world, but it is uniquely characterized by the qualities which its reduction to mathematical laws necessarily emphasized. (232)
The gloriously romantic universe of Dante and Milton, that set no bounds to the imagination of man as it played over space and time, had now been swept away. Space was identified with the realm of geometry, time with the continuity of number. The world that people had thought themselves living in—a world rich with colour and sound, redolent with fragrance, filled with gladness, love and beauty, speaking everywhere of purposive harmony and creative ideals—was crowded now into minute corners in the brains of scattered organic beings. The really important world outside was a world hard, cold, colourless, silent, and dead; a world of quantity, a world of mathematically computable motions in mechanical regularity. The world of qualities as immediately perceived by man became just a curious and quite minor effect of that infinite machine beyond. In Newton the Cartesian metaphysics, ambiguously interpreted and stripped of its distinctive claim for serious philosophical consideration, finally overthrew Aristotelianism and became the predominant world-view of modern times. (238-9)
It was difficult for thinkers really to carry through Descartes' bold suggestion that everything in the world that is not mathematical is to be shoved into human minds as a mode of thought.... (265)
[Are sensible objects distinct from their subjectively sensed qualities?] In practice we correct dubious perceptions by appealing to further perceptions; we never correct them by comparison with something unperceived. (316)
... it does seem like strange perversity in these Newtonian scientists to further their own conquests of external nature by loading on mind everything refractory to exact mathematical handling and thus rendering the latter still more difficult to study scientifically than it had been before. (320)
On Final Causes
The moderns likewise sought to eliminate teleology or purposes from the objective, non-human world. This movement began before Descartes, as for example, in Machiavelli, though Burtt doesn't discuss this line of precedents. Of the major figures in the book, Boyle seemed to me the most sympathetic, and teleology was one issue on which he seemed close to correct.
But Descartes is not much interested in the res cognitans, his descriptions of it are brief, and, as if to make the rejection of teleology in the new movement complete, he does not even appeal to final causes to account for what goes on in the realm of mind. Everything there is a mode of the thinking substance. (119)
Boyle's chief points of disaffection with Descartes were the latter's banishment of final causes on the ground that we cannot know God's purposes, and his main postulates about motion. The English thinker holds it obvious that some of the divine ends are readable by all, such as the symmetry of the world and the marvelous adaptation of living creatures, hence it is foolish to reject teleological proofs of the existence of God. (169)
[Boyle] proposes to use the term form, for example, to mean (instead of the scholastic essential qualities) "those mechanical affections necessary to constitute a body of that determinate kind." Nature, too, he wishes to rescue from the vague and varied uses to which it had been put in ancient and medieval discussions, and define it in terms of the new dualism—it is not a collection of substances not a mysterious wielder of incalculable forces, but a system of mechanical laws, i.e., it is the world of matter and motion distinct from rational souls and immaterial spirits. (177)
Boyle criticized teleological explanations; the validity of final causality, unlike Descartes and Hobbes, he does not at all call into question, but points out that an answer to the ultimate why of anything is no substitute for an answer to the immediate how. "For to explicate a phenomenon, it is not enough to ascribe it to one general efficient, but we must intelligibly show the particular manner, how that general cause produces the proposed effect. He must be a very dull inquirer who, demanding an account of the phenomena of a watch, shall rest satisfied with being told, that it is an engine made by a watchmaker; though nothing be thereby declared of the structure and coaptation of the spring, wheels, balance, and other parts of the engine, and the manner, how they act on one another, so as to co-operate to make the needle point out the true hour of the day." (178)
It is important indeed for the onward march of the new philosophy of science that Boyle's acceptance of teleology as a valid metaphysical principle did not lead him to apply it in physics; here he follows his predecessors in holding that the immediate and secondary cause of any effect is always a prior motion of some sort. (179)
[Boyle:] "But inanimate bodies are utterly incapable of understanding what a law is... and therefore the actions of inanimate bodies, which cannot incite or moderate their own actions, are produced by real power, not by laws." This thought, that inasmuch as the world cannot know what it is doing, its orderly and law-abiding behavior must be accounted for by real, constant, intelligent power, occurs in other passages in Boyle. Nowhere is there any clear attempt to reconcile this with the position that the laws of motion and the phenomena of gravity represent quite self-sufficient mechanical operations. (199)
Now it may well be that science, despite its rejection of final causes, reveals the presence and functioning of values in the fundamental categories it selects and the way it applies them. If so, then an adequate scientific metaphysic will not be able to manage without teleology in some form, and it becomes a question of first-rate importance what that form is to be. (310)
On Space and Time
In a purposeless universe, no place can be any more special than another; bodies move blindly in a featureless void. At Newton's hands, space and time were absolutized, that is, given an existence apart from the rest of the world, as if they were containers waiting for bodies to fill them. According to Burtt, this source of this assumption comes from the theology fashionable at the time.
Just as space had ceased [in the sixteenth century] to appear accidental to objects and relative to magnitudes, and became a vast, infinite substance existing in its own right (except for relation to God) so time ceased to be regarded as merely the measure of motion, and became a mysterious something ultimately of religious significance, but quite independent of motion, in fact measured now by it, flowing on from everlasting to everlasting in its even mathematical course. From being a realm of substances in qualitative and teleological relations the world of nature had definitely become a realm of bodies moving mechanically in space and time. (161)
The ethereal medium, whatever may be said about tangible bodies, was not a mere machine [according to More]. If it were, the universe would rapidly dissipate, by the first law of motion. Qualities and powers were assumed in it which were not mechanical. Therefore it must be spiritual, incorporeal, the active executor of the divine will, holding the frame of the world together in the phenomenon of cohesion, magnetism, gravity. At the same time its effects are regular and orderly, doubtless reducible to exact scientific law. All this complex of ideas was shared by Boyle, and passed from More and Boyle to Newton, in whose philosophy it played a distinctive part. (166-7)
[H]ow does Newton, the experimentalist and ejector of hypotheses, dare to introduce [absolute space, time, and motion] with his definitions of mass an force and his axioms of motion? How, even, we might add, would be he able to tell whether this hypothetical celestial body were really at rest in absolute space, even though it fell under our observations, inasmuch as space by its own nature is infinite and homogeneous, its parts indistinguishable from each other? (249)
But thus far alone we can go with Newton; no farther. For note: absolute space and time as thus understood, by their own nature negate the possibility that sensible bodies can move with reference to them—such bodies can only move in them, with reference to other bodies. Why is this so? Simply because they are infinite and homogeneous entities; one pat of them is quite indistinguishable from any other equal part; any position in them is identical with any position; for wherever that part of position may be it is surrounded by an infinite stretch of similar room in all directions. Taking any body or system of bodies by itself, therefore, it is impossible to say intelligibly that it is either moving or at rest in absolute space or absolute time; such a statement only becomes meaningful when another phrase is added—with reference to such and such another body. things move in absolute space and time, but with reference to other things. A sensible centre of reference must always be definitely or tacitly implied. (256-7)
[T]ime is conceived as a homogeneous mathematical continuum, extending from the infinite past to the infinite future. Being one and entire, its whole extent is somehow present at one; it is necessarily bound together and all subject to knowledge. The laws of motion, together with the doctrine of the constancy of energy, inevitably result in this picture of the whole sweep of time as a realm mathematically determined in terms of an adequate present knowledge. But carry this conception to the limit, and does not time quite disappear as anything ultimately different from space? Once the Platonic year is discovered, everything that can happen is a present event. (263)
[T]he space of perception is too much like the space of real objects to reveal any essential difference from it. All it needs is to be freed from illusions, private images, and other experiences lacking social objectivity, to function quite acceptably as real space. And once this point has been reached there seems no longer any excuse for maintaining the distinction between sensed qualities and the real characters to which they correspond. (317)
On God and His Relationship to the Universe
In the heterodox climate of post-Reformation England, all sort of weird beliefs flourished, and, according to Burtt, this was the unexamined source of many presumptions on which scientific investigations were based. This is not to say that some fundamental Christian beliefs did not manage to shine through.
Barrow's religious interest appears above all in his postulate of the constancy of nature; he goes on to affirm that all demonstration presupposed the existence of God. "I say that all demonstration assumes the truth of hypotheses [postulates, we should say]; the truth of an hypothesis attributes to the thing which is assumed a possible existence; this possibility involves an efficient cause of the thing (otherwise it would be impossible for it to exist); the efficient cause of all things is God." (155, bracketed insert by Burtt)
[Barrow reasoned that] God can create worlds beyond this world, hence God must extend beyond matter, and it is just this superabundance of the divine presence and power that we mean by space. (155)
It is noticeable, however, that Boyle is eager not to overstress the importance of miracles; the main argument for God and providence is the exquisite structure and symmetry of the world—regularity, not irregularity... (201)
From the Protoplast of the whole, God has now descended to become a category among other categories; the facts of continued order, system, and uniformity as observed in the world, are inexplicable apart from him.... [In the scholastic system] God had no purpose; he was the ultimate object of purpose. (297)
How could intelligence grasp an inaccessible world in which there was no answering or controlling intelligence? It was by no means an accident that Hume and Kant, the first pair who really banished God from metaphysical philosophy, likewise destroyed by sceptical critique the current overweening faith in the metaphysical competence of reason. (301)
Miscellaneous
Burtt's book is full of interesting historical facts and insightful observations. Here are a few that don't fit into any of my categories. I particularly appreciate Boyle's rejection of the practice of the time of thinking of spirits as somehow material.
In fact, we know that, by many, astronomy was regarded as closer to the geometrical ideal of pure mathematics than arithmetic. Typical lists of the mathematical sciences offered by Alfarabi and Roger Bacon place them in the order: geometry, astronomy, arithmetic, music. (46)
Galileo himself remarks that Aristotle would change his opinion if he saw our new observations, for his method was essentially empirical. "I do believe for certain that he first procured, by the help of the senses, such experiments and observations as he could, to assure him as much as was possible of the conclusion, and that he afterwards sought out the means how to demonstrate it; for this is the usual course in demonstrative sciences. And the reason thereof is, because when the conclusion is true, by the help of the resolutive method, one may hit upon some proposition before demonstrated, or come to some principle knowns per se; but if the conclusion is false, a man may proceed in infinitum, and never meet with any truth already known." (78)
Further, it is to [William] Gilbert's experiments on magnetism that we owe the first beginnings of the use and conception of the word "mass" as we find it later matured in Newton. According to Gilbert, the strength and reach of a loadstone's magnetism varies with its quantity or mass, that is, if it be of uniform purity and from a specified mine. Galileo and Kepler borrowed the notion of mass from Gilbert in this sense and connexion. (164)
Boyle is eager to affirm, however, in refutation of Hobbes, that this applies only to secondary causes—to assert absolutely that motion is impossible except by a body contiguous and moved, is to involve oneself in an infinite regress and to deny ultimate causality by a spiritual deity. (180)
[Boyle rejects More's doctrine of spirits having extension and holds spirits to be immaterial and immortal.] "When I say that spirit is incorporeal substance... if he should answer, that when he hears the words incorporeal substance, he imagines some aerial or other very thin, subtile, transparent body, I shall reply, that this comes from a vicious custom he has brought himself to, of imagining something whenever he will conceive anything, though of a nature incapable of being truly represented by any image in the fancy." (183-184)
Newton was thus the common heir of the two important and fruitful movements in the preceding development of science, the empirical and experimental as well as the deductive and mathematical. He was the follower of Bacon, Gilbert, Harvey, and Boyle, just as truly the successor of Copernicus, Kepler, Galileo, and Descartes; and if it were possible to wholly separate the two aspects of his method, it would have to be said that Newton's ultimate criterion was more empirical than mathematical. (213-4)
[To Newton,] anything that is not immediately deduced from the phenomena is to be called an hypothesis and has no place in science, especially attempts to explain the nature of forces and causes revealed in the phenomena of motion. (226)
(Perhaps I should have included the last passage in the previous post.)
E.A. Burtt, Metaphysical Foundations of Modern Science (Garden City, NY: Doubleday and Company, 1954). Same pagination as Dover Books edition.
