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in such sense and as properly as it is se id to reside in animal bodies. It
must neverthelest be owned, that albeii that philosopher achnowledgetha divine force or energy in fire, yet to say that fi re is alive, or that havinga so ut it mould not be alive, stem to him equalty absurd. See his secondbook, de partibus animalium.
23 I. The laws os attraction and repulsion are to be regarded as la sos motion, and these only as rules or methods observed in the productions os natural essects, the efficient and final causes whereos a re not of mechanical consideration. Certa inly, is the explaining a Phaenomenon be to assign iis proper efficient and final cause , it should seem the mechanical philosophers ne ver expla ined any thing; their province be ingonly to disco ver the laws of nature, that is the generat rules and method sos motion, and to account for particular phaenomena by reducing themunder, or shewing their conformi ty to lacti generat rules. 232. Some corpuscularian philosophers of the last age, have in deed attempted to explain the formation of this worid and iis phaenomena, bya se is simple laws of mechanita. But is we consider the Various productions os nature, in the minerat, vegetabie, and animal paris of the creation, I belle ve we shali ste cause to affirm, that not any one of them has hi therio been, or cara be accounted for on principies merely mechanical , and that nothing could be more vain and imaginary, than to su in Post With Dcscat tes, that merely frona a circular motion's being impresscd by the supreme agent on the particles of extend d substance, the wholeworld with ali iis severat paris, appurten ances, and phaenomena might be produced, by a necessary consequence stom the laws of motion. 233. Others suppo se that God did more at the begintaing, having thenmade the secds of ali vegetabies and animais, containing their solid or-
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ganical paris in miniature, the gradual fili ing and evolution os whicli, by the influx of proper juices, doth constitute the generation and growthos a living body. So that the artificiat structu re os planis and animais
dat ly generate i, requires no present exerci se of art to produce it, hau ingbeen atre ady framed at the origin of the worid, which with ali iis paris halli ever since subsisted, go ing like a clock or machine by itself, accord-Ing to the laws of nature, without the immediate hand of the artist. But how can this hypothesis expla in the blended statu res of different
species in mules and other mong reis ρ or the paris added or Charaged, and sornetimes whole limbs tost by ma rhing in the wombi or how can it account sor the resurrection os a tree frona iis stumi , or the vegetati vel ower in iis c ut tings t in whicli cases we must necessari ly concesve so mething more than the mere evolution os a seed. 23 . Mechanical laws of nature or motion direct us how to act, andieach us what to expect. Whcre intellect presides there will be methodand order, and there re rules, whicli is not sta ted and constant would Cea se to be rules. There is there re a constancy in things, whicli is styled the cour se of nature '. All the phaenomena in nature are produced by motion. There appe ars an uni sorm Wrorking in things great an d sinati, by attracting and repelling sorces . Eut the particular Ja s of attraction and repulson a re various. Nor aro we concerned at ali about the forces, ncither can we know or meastare them other i se than by their
essedis, that is to say the motions, whicli motions Only, and not thesor es, a re indeed in the bodies '. Eodios a re moved to or Dorn e achother, and this is persormed according to disserent la s. The natural ormechanic philosopher en dea voiars to disco ver tho se la s by experimentand rea ning. But what is se id os sordes residing in bodies, whether at-etracting or repelling, is to be regarded Cnly as a mechanical hypothesis,md not as any thing reatly existing in nature.
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et 35. We a re not there re seriousy to suppose with ocria in mechanicphilosophers, that the minute particles of bodies have real forces or powers, by whicli they act on each other, to produce the Various phaenomena in nature. The minute corpuscles a re impelled and directed, that is tosay, moved to and Dom ea ch other according to vario us rules or laws of motion. The la s of gravi ty, magnetistia, and electrici ly a re divers. And it is not known, What other disserent rules or laws of motion mighthe est ablimed, by the author os nature. Some bodies approach together, others sy astander, and perhaps sonae others do ne i ther. When sali os tartar flows per deliquium, it is visi ble that the particles of water Boat ingin the air a re moved to ards the particles of sali, and joined with them. And when we belloid vulgar fati not to flow per deliquium, may we notconclude that the fame law of nature and motion doth not obta in be- tween iis particles and those of the floating Vapourst A drop of wate fassumes a round figure, because iis part S are moved toWard S each other.
But the particles of Oil and vi negar have no fuch disposition to unite. And when 1lies Walli in water without wetting their seet, it is attribute dto a repelling force or faculty in the sile's seel. But this is obscure, though the phaenomenon be plain. 36. It is not improbabie, and seems not un supported by experimenis, that, as in algebra, Where positive quantities cease there negati vehegin, even se in mechanies, Where attracting forces Cease there re
lo be moved toWards, they begin to be moved stom each other. ThisSit Isaac Newton insers frona the productiora os air and Vapo tars, whose particles sty alander With fuch vehement force. We belloid iron movelowards the loadstone, stra Ws to ards amber, heavy bodies towariis theearth. The laws of these motions are various. And when it is se id that ali the motions and changes in the great worid ari se stom attraction: the elastici ty of the air, the motion of water, the descent of heavy, and
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the ascent of light bodies, being ali ascribed to the same principie; when
from insensibi e attractions of most minute particles at the smallest dis. tance, are derived cohesiora, dissolution, coagulation, animal secretion, fermentation, and ali chymicat operations; and when it is sa id, that without such principies there ne ver Would have been any motion in the Worid, and without the continuance thereos ali motion would cease. Inali this we linow or understand no more, than that hodies are moved according to a certain order, and that they do not move themselves. 237. So likewise, how to expla in ali those various motions and essedis,
by the dens ty and elastici ty of aether, seems incomprehensibi e . Forinstance, why mould the acid particles draw those of water and repeleach other 8 why should me salis attrast vapoiars in the air, and othetanott why should the particles of common sali repet Cach other, as notio subside in watery why should the most repellent particles be the most attractive upon contact y Or why should the repellent begin where theat tractive faculty leaves Osf. These, and numberlesis other essests seem inexplicabie on mechanical principies, or otherwise than by recour se to amind or spiritual agent l. Nor will it sussice stom present phaenomena and effecis, through a cha in of natural causes, and subordinate bl indagenis, to trace a divine intellecit as the remote original cause, that sirst creat ed the worid, and then set it a going. We cannot malle even ΟΠe
single step in accounting for the phaenomena, without admitting the immediate presence and immediate action of an incorporeat agent, Whoconnecis, moves, and disposes ali things, according to such rules, and forsu cli purposes as seem good to hi m. 238. It is an old opinion adopted by the moderns, that the elements and other natural hodies are changed ea ch into other t. Now, as the particles of different hodies a re agitated by different forces, attracting
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and repelling, or, to si eali more accurately, a re moved by different laws,hON Can these forces or lawS be changed, and this change accounted forby an elastic aetheri Such a medium distinet frona light or fire se emethnot to made out by any proos, nor to be of any use in explaining the Phaenomena. But is there bo any medium employed, as a subordinate Cause or instrument in attraction, it would rather feem to be light'; since by an experiment of Mr. Boyle's, amber, that shewed no sign ofattraction in the made, heing placed where the sun-beam S shone u ponit, immediately attracted light hodies. Eessides, it hath been disico vered by Sir Isaac Newton, and an admirabie disco very it mras, that light is an heterogeneous medium ' consisting of particles en dued with original di tinct properties. And upon these, is i may VentUre to give my conjectures, it seemeth probable the specific properties of bodies, and the Orce of specific medicines may depend. Disserent sides of the fame ray shall, one approach and the other recede frona the istandic crystal; can this beaccounted sor by the elastici ty of a fine medium, or by the generat lawsos motion, or by any mechanical principies Whate ver i And is not, whatshould hinder but there may be specific medicines, whose operation de-Pends not Upon mechanical principies, how much Qe ver that notion hathbeen exploded os late years t239. Why may R e not suppose certa in idiosyncrastes, sympathies, oppositions, in the solids or fluids or animal spirit of a human body, withregard to the fine insensibie paris of minerals or vegetabies, impregna ted by rays of light os different properties, not depending on, the different si Ze, figure, number, solidi ty or Height of tho se particles, nor On thegenerat laws of motion, nor ori the ciensi ty or classici ty of a medium, butmerely and altogether on the good plea sure of the Creator, in the original formation of thingst From whence divers unaccountable and un- foresten motions may ari se in the animal oeconomy; Dom Whence also
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Siris. vario us peculiar and specific viriues may be conceived to arise, residingin certa in medicines and not to be explained by mechanical principies. For although the general known laws of motion a re to he dee med mechanical, yet peculiar motions of the insensibi e paris, and peculiar properties depending thereon, are occuli and specific. 2 O. The words attraction and repulsion may, in compliance with custom, be used where, accurately speahing, motion alone is meant. An d in that sense it may be suid, that peculiar attractions or repulsions in the paris, a re attended with specific properties in the whole. The particles of light are vehemently moved to or stom, reta ined or rejected
by objects. Whicli is the fame thing as to say with Sir Isis ac Newton,
that the particles of acilis are eradu ed with great attractive force ', where in their activi ty consi sis; whence fermentation and dissolution ;and that the most repellent a re, upon contact, the most attracting par
et I . Gravi ty and sermentation are received sor two most extensive principies. From fermentation a re derived the motion and war mlh of the heari and blood in animais, subterraneous fleat, si res, and earth- quakes, meteors and changes in the atmosphere. And, that attractingarid repelling forces operate in the nutrition and dissolution os animal and vegetable bodies, is the doctrine both of Hippocrates and Sir Isaac Newton. The former of these celebrated authors, in his treati se concerning diei or regimen, observes that in the nourishment of man, one pari repeis and another attracis. Arad again in the sume treati se, two carpen- ters, salth he, saw a pie ce of timber: one dra s, the other pus hes : the two actions tend to one and the fame end, though in a contrary direction, o ne up, the other do n : this imitates the nature of man : o
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a a. It is the generat maxim os Hippocrates, that the manner Wherein nature aius consisteth in attracting What is meet and good, and in repelling what is di greeable or huri l. He mahes the whole of the animaloeconomy to be administered by the faculties or powers of nature. Naature alone, Lith he, sufficeth for ali things to animais. She knows of herself what is necessary for them. Whence it is plain, he mcans a conscious intelligent nature, that presides and moves the aetheriat spirit. And though he declares ali things a re accompli med ora mala by necesii ty, yet it is not a bli ad fate or cha in Os mere corporeat causes, but a divine necesii ty, as he himself expressy calis it. And what is this but an overtaruling intelligent power that disposeth of ali thingstet a. Attraction cannot Produce, and in that sense account sor thephaenomena, being itself one of the Phaenomena produced and to beaccounted for'. Attraction is peri Ormed by different laws, and cannotthere re in ali cases be the effect of the elastici ty of one uni rin me dium. The phaenomena os electrical bodies, the laws and variations os magneti si , and , not to mention Other kinds, even gravi ty, is not explain-ed by elastici ty, a phaenomenon not lese obscure than itself But then, although it meis not the agent, yet it me eth a rule and analogy in nature, to say, that the solid paris of animais are eradu ed with attractive powers where by fro in contiguous suids they draw like to like , and that glands have peculiar po ers attractive os peculiar juices '. Nature Dems helter known and expla ined by attractionS and repulsions, than by thoseother mechanical principies of sige, figure, and the like: that is by Sir Isaac Newton, than Doscartes. And natural philosophers excel, as theyare more or lese a qua in ted with the laws and methods observed by the
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ne ver explain the secretions Without the hel p os attraction, obscure per-haps as to iis cause, but clear as a law. Num berte sis instances of thismight be gi vera: Lemery the yo unger thought hiriasielf obliged to suppose the particles of light or fire contrary to ali rea n) to be of a very grosskind, even greater than the pores of the burrat limesione, in order toaccount for their being detained or imprisoned therein; but this phaenomenon is ea si ly redueed to attraction. There would he no end of enumerat ing the like cases. The activi ty and force of aetheriat spirit or si re by the laws os attraction, is imparted to grosser particles and therebywonder i ly supporis the oeconomy of living bodies. By such peculiarcompositions and attractions it stems to be effected, that denser fluid scata pass where air it self cannot, as Oil through leat hor) and thereserethrough the nicesi and finest strainers of an animal or vegetable.
Pelling po ers ' as natural principies. Galilaei had particularly consider-ed the attraction os gravi ty, and made so me disco very of the lari s there- M. But Sir Isaac Newton by his singular penetration, pro und knowledge in geometry and mechanics, and great exactnesi in experimen is,hath cast a new light on natural science. Thc laws of attraction and repulsion were in many instances disco vered, and first disco vered by him. He shewed their generat extent, and thereis illi as with a key ope ned severat deep secrets of nature, in the linowledge whereos he seems to have made a greater progress, than ali the sedis of corpuscularians together had done besore hi m. Nevertheless, the principie os attraction iiself is not to be explained by physical or corporeat causes.
element, receding Dom the center of iis motion, and impelling grosser
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bodies towards it. Sir Isaac Newton in his later thoughis seems as wasbe re observed) to have adopted semewhat not altogether fore ign Domitiis notion, ascribing that to his elastic medium ' whicli Descartes did tollis second element. But the great men os antiqui ty resolved gravi ty into the immediate action os an intelligent incorporeal being. To whicli alta Sir Isaac Newton himself attests and subscribes, although he may pertia semetimes be thought to larget himself, in his manner of spea Ling of physical agenis whicli in a strict sense a re non e at ali; and in supposita great forces to exist in hodies, in which, to spe ali truly, attraction and repulsion should be considered only as tenden cies or motion S, that iS, as mere esiacis, and their laws as laws of motion.
ψ . Though it be supposed the chi es busine si os a natural philosopherto trace out causes Dom the es dis, yet this is to be understood not ofagenis ' but of principies, that is os component PariS, in one sense, . oros laws or rules in another. In siridi truth, ali agents are incorporeat, and as such are not properly of physical consideration. The astronomer, there re, the mechanic, or the chymist, not as lach, but by accidentonly, treat os real causes, agents or essicients. Nei ther doth it stem, asis supposed by the greatest of mechanical philosophers, that the triae
way of proceed ing in their science is, seo in linown motions in natureto investigate the moving forces. Forasmuch a S rce is nei ther corpo real nor belongs to any corporeat thing n Ox yet to be discovered by experiments or mathematical rea nings, whicli reacti no farther than dis cerni ble esiacis, and motions in things passive and moved. et 8. Vis or Orce is to the foui, What extension is to the hody, salth St. Augustin, in his trach concerning the quantity of the foui; and without sorce there is nothing done or made, and consequently there can bem
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no agent. Authori ty is not to decide in this case. I et any one consulthis own notions and re ason, as weli as experience, concerning the originos motion, and the respective natures, properties, and differen ces of Duland body, and he will, is I mista ke not, evident ly perceive, that there is nothing active in the lalter. Nor are they natural agents or corporealforces, which mahe the particles of hodies to cohere. Nor is it the busin est os experimental philosophers to find them oui. 2 9. The mechanical philosopher, as liath been at ready observed, en quires properly concerning the rules and modes of Operation alone, and not concerning the cause, forasmuch as nothing mechanicat is or reatly Can be a cause . Arad although a mechanical or mathematical philosopher may speali os absolute space, absolute motion, and of sorce as existing in bodies, causing suci, motion and proportionat thereio; yet what these forces are, whicli are suppo sed to be lodged in bodies, to be impressed on bodies, to be multiplied, divided, and communica ted Domone body to another, and whicli stem to animate hodies like abstractspiriis, or Quis, hath been Gund very dissiculi, not to say impossibie, sortii in hing men to conceive and explain, as may be seen by consultingBorellus de vi percussonis, and Torricelli in his Detioni academiche, among
2so. Nor, is we consider the proclivi ty of manliind to realige their notions, will it stem strange that mechanic philosophers and geometricians mouid, like other men, be missed by prejudice, and talae mathematical hypotheses, sor real beings existing in hodies, so far as evento mahe it the very aim and end of their science to compute or mea lare those phantoms ; whereas it is very certain that nothing in truth