## 1. Life



Robert Boyle was born in Lismore, Ireland, on January 25, 
 1627.[6]
He was his parents' fourteenth, penultimate, child, and the last
to survive to adulthood. Boyle was the youngest son and, after his
sister Margaret died when he was 10, the youngest child of the
family. Boyle speaks fondly of his parents, but he could not have
known them well. His mother died in childbirth a few weeks after
Boyle's third birthday, and he last saw his father just before
he and his brother Francis left for a continental tour when Boyle was
twelve.



Like many children Boyle had his share of near escapes from serious
injury as a child, but the time and Boyle being what they were he saw
in each of them the hand of God. Michael Hunter has pointed out that
"the spiritual autobiography, aimed at chronicling God's
purpose for the individual in question by recounting providential
escapes, spiritual trials and conversion experiences," was
"a characteristic genre of autobiographical writing in
seventeenth-century England" (Hunter 1994a, xx), and Nicolas
Canny notes that "The invocation of providence as an explanation
for accidental or chance happenings in this life was so commonplace
among sincere Protestants in the early seventeenth century that it had
come to be considered irreverent or profane not so to attribute
them" (Canny 1982, 28). But, though common enough, there is no
doubt that, in Boyle's case at least, the protestations were
sincere. He continued to believe in this divine attention, though in a
more intellectual realm, throughout his life. In 1663 he wrote,



> 
> And though I dare not affirm ... that God discloses to Men the
> Great Mystery of Chymistry by Good Angels, or by Nocturnal Visions
> ... yet perswaded I am, that the favor of God does (much more
> than most Men are aware of) vouchsafe to promote some Mens Proficiency
> in the study of Nature (Boyle Works [BW], 3:276, Birch 1772,
>  II:61).[7]
> 


### 1.1 The Grand Tour



In Geneva on his continental tour Boyle underwent what he clearly felt
to be a conversion from nominal or at least unthinking Christianity to
committed Christianity. One summer night, he "was suddenly waked
in a Fright with such loud Claps of Thunder ... & every clap
... both preceded & attended with Flashes of lightning so
numerous ... & so dazling, that [he] began to imagine
... the Day of Judgment's being come." This led him
to vow that "all further additions to his life shud be more
Religiously & carefully employ'd." Realizing the
inefficacy of a promise exacted under duress, Boyle repeated the
performance under a serene and cloudless sky "so solemnly that
from that Day he dated his Conversion; renewing now he was past
Danger, the vow he had made whilst he fancy'd himselfe to be in
it: that tho his Feare was (& he blush't it was so) the
... occasion of his Resolution of Amendment; yet at least he
might not owe his more deliberate consecration ... of himselfe to
Piety, to any less noble Motive then that of it's owne
Excellence" (BP 37:181r-v, Hunter 1994a, 16).



The promise seems never to have been broken, and indeed the later
Boyle stressed the need to have an *examined* faith. He pointed
out that "usually, such as are born in such a place, espouse the
opinions true or false, that obtain there" (BW, 12:421, Birch
1772, VI:712), indeed, "the greatest number of those that pass
for Christians, profess themselves such only because Christianity is
the religion of their Parents, or their Country, or their Prince, or
those that have been, or may be, their Benefactors; which is in effect
to say, that they are Christians, but upon the same grounds that would
have made them Mahometans, if they had been born and bred in
Turky" (BP 7:233, BOA SS3.7.5, pp 301-2). Boyle felt
that more was required of the thinking believer. Locke agreed: often a
child's notion of God does more "resemble the Opinion, and
Notion of the Teacher, than represent the True God" (Essay,
1.14.13).



Hard on the heels of Boyle's enlightenment, doubts about his
faith began to trouble
 him,[8]
 and these "distracting Doubts of some of the Fundamentals of
Christianity" continued: "never after did these fleeting
Clouds, cease now & then to darken ... the clearest serenity
of his quiet: which made him often say that Injections of this Nature
were such a Disease to his Faith as the Tooth-ach is to the Body; for
tho it be not mortall, 'tis very troublesome" (BP 37:182r,
Hunter 1994a, 17).



Leaving Switzerland, Boyle, along with Marcombes and his brother
crossed the Alps and entered Italy in September 1641 where, in
Florence, he spent the winter. "In *Italy* he read over
the lives of the ancient philosophers with the utmost
attention," presumably in Diogenes Laertius, and "[t]he
sect, which then struck him most, was that of the Stoics; and he tried
his proficiency in their philosophy, by enduring a long fit of the
tooth-ach with great
 unconcernedness."[9]
 Still in Italy he had (in the winter of 41-42) what seems to
have been one of the very few sexual encounters of his life. Writing
about himself in the third person as Philaretus (sometimes P., or
Filaretus) he says:



> 
> Nor did he sometimes scruple, in his Governor's Company, to
> visit the famousest Bordellos; whither resorting out of bare
> Curiosity, he retain'd there an unblemish't Chastity,
> & still return'd thence as honest as he went thither.
> Professing that he never found any such sermons against them, as they
> were against themselves. The Impudent Nakednesse of vice, clothing it
> with a Difformity, Description cannot reach, & the worst of
> Epithetes cannot but flatter. But tho P. were noe Fewell for forbidden
> Flames, he prov'd the Object of unnaturall ones. For being at
> that Time not above 15, & the Cares of the World having not yet
> faded a Complexion naturally fresh enuf; as he was once
> unaccompany'd diverting himselfe abroad, he was somewhat rudely
> presst by the Preposterous Courtship of 2 of those Fryers, whose Lust
> makes no distinction of Sexes; but that which it's Preference of
> their owne creates; & not without Difficulty, & Danger,
> forc't a scape from these gown'd Sodomites. Whose Goatish
> Heates, serv'd not a little to arme Filaretus against such
> Peoples specious Hyprocrisy; & heightn'd &
> fortify'd in him an Aversenesse for Opinions, which now the
> Religieux discredit as well as the Religion (BP 37:184r-v, Hunter
> 1994a, 20).
> 



Leaving Italy Marcombes and the two boys found on arrival in
Marseilles that the monies the Great Earl had been in the habit of
sending were no longer to arrive and that, indeed, the last
quarter's payment had been held up by Cork's London agent.
Moreover, there was a letter from the Earl, unaware of the mischance
affecting the quarterly payment, telling them that, as a result of the
rebellion in Ireland, no more money was to be forthcoming: in the
"dangerous and poore estate whereunto by gods providence"
he had been reduced, he had "with much difficulty gott together
two hundred and fifty pounds by selling of plate," but to pay
Marcombes' bills punctually as he had in the past "I am
noe waies able." So he advised Marcombes to use the money to
bring the two boys



> 
> out of some meet port in France to land either at dublin, Corke, or
> Youghall, (for all other Cities and Sea townes are possessed by the
> enemy), or else my two sonnes [must] travaile into Holland, and putt
> themselves into entertaynement under the service and conduct of the
> Prince of Orange; for they must henceforward maintayne themselves by
> such entertaynements as they gett in the warres (Earl of Cork to
> Marcombes 9 March 1641/2, Maddison 1969, 47).
> 



In the event Francis decided to return to Ireland, arriving in time to
fight in the Battle of Liscarrol (September 3, 1642), at which another
Boyle brother, Lewis, was killed. Meanwhile Robert decided that his
health and lack of money ruled out a return to Ireland, and his age
made soldiering in Holland an untempting and indeed implausible
 prospect.[10]
 He therefore decided to accept Marcombes' offer of hospitality
in Geneva, and did not make his way to England until the summer of
1644.



Before leaving Geneva Boyle had a conversation with Francois
Perreaud (1572-1657), who later wrote *Demonographie,
ou traite des demons*, which Boyle then arranged to
have translated into English by Peter du Moulin (the younger,
1601-1684). In a letter prefixed to the English edition Boyle
recalled that "the conversation I had with that pious Author
during my stay at *Geneva*, and the present he was pleased to
make me of this Treatise before it was printed, in a place where I had
opportunities to enquire both after the writer, and some passages of
the booke, did at length overcome in me (as to this narrative) all my
settled indisposedness to believe strange things." (BW 1:15)
Acceptance of at least the *possibility* of diabolic or angelic
intervention was common among the intelligentsia in the second half of
the seventeenth century. Cudworth pointed out one expedient reason for
the belief:



> 
> all these *Extraordinary Phaenomena*, of Apparitions,
> Witchcraft, Possessions, Miracles, and *Prophecies*, do Evince
> that *Spirits, Angels or Demons*, though *Invisible* to
> us, are no *Phancies*, but *Real and Substantial*
> Inhabitants of the World; which favours not the *Atheistick
> Hypothesis;* but some of them, as the Higher kind of Miracles, and
> Predictions, do also immediatly enforce the acknowledgment of a
> *Deity*: a Being superiour to *Nature*, which therefore
> can check and controul it; and which comprehending the whole,
> foreknows the most *Remotely distant*, and *Contingent
> Events* (Cudworth 1678,
>  715).[11].
>  



In a manuscript draft ("Loose papers whence some things are to
be extracted for the Discourse of the causes of Atheism") Boyle
considered three objections that might be made against such a belief:
the implausibility of the standard means of bringing about such
intervention; the unreliability of the witnesses; and the
impossibility of incorporeal beings interacting with matter. He agrees
that the first objection, "urg'd with great confidence,
and not without much show of Reason" is a strong one, but
suggests that "we men understand very little of the nature,
customes, & government of the Intelligent creatures of the
spirituall world: and particularly what concernes the Falne Angells or
bad Daemons. And therefore they being themselves invisible to us, and
capable of working in wayes that our sences cannot discerne; and being
Agents of great craft & long experience; tis no wonder that many
of their actions, tho never so pollytickly contrived &
carried on, should seem irrationall to us: who know so little of their
particular inclinations & designes, and the subtil & secret
methods in which they carry them on."



The second objection he also accepts, though not wholly:
"tho upon particular & cogent proofe I beleeve some of
them to be true ... yet I reject or distrust far the greatest
part, as not being soe attested." The third he rejects as being
simply inconsistent, for the human soul is accepted as incorporeal,
and it works (though we know not how) on matter (BP 2:105, BOA
SS3.5.21, pp 257-8).



When Boyle arrived back in England in mid-1644 at the age of 17 he was
quickly reunited with his sister Katherine who seems immediately to
have re-adopted the semi-maternal role she had no doubt often played
after the death of their mother. She was concerned in a variety of
other ways to look after his welfare, both spiritual and worldly. She
was, for example, the immediate cause of his getting to know the
members of the Hartlib
 circle.[12]



At this time Boyle settled in Stalbridge (on an estate left to him by
his father) and occupied himself mainly in writing or planning works
in ethics and theology. Much of his time during the early part of this
Stalbridge period was spent in moral philosophy -- "My
*Ethics* go very slowly on," he wrote to his sister
Katherine on March 30, 1646 (BC 1:34) -- and there was at this
stage no reason to think that he would become one of the great natural
philosophers of his time. (See further, Hunter 2009, chs. 4 and 5;
Corneanu 2020.) He already approximated to the
"lay-bishop" that Aubrey, quoting Anthony Walker, was
later to find him to be. He was, in fact, a serious, somewhat priggish
young man, though he often gave signs of light-heartedness both as a
boy and in later life. After his death Gilbert Burnet claimed that
"As for Joy, he had indeed nothing of Frolick and Levity in
him," a judgement accepted by Steven Shapin, but this fails to
allow for the lighter moments that Boyle undoubtedly
 enjoyed.[13]


### 1.2 The turn to natural philosophy



At Stalbridge, about 1649, Boyle began to be interested in
experimenting, but was hindered by the fact that he could not obtain a
furnace. Stalbridge was far enough away from tradespeople who could
make such an item and the furnaces Boyle ordered tended to arrive
"crumbled into as many pieces, as we into sects," leaving
Boyle to attempt "such experiments, as the unfurnishedness of
the place, and the present distractedness of my mind, will permit
me" (BC 1:50).



Boyle was troubled throughout his life by the fragmentation of
Christianity. Among "the giddy multitude ... this
multiplicity of religions will end in none at all," he wrote to
John Mallet in
 1652,[14]
 and at the very end of his life he expressed in his Will the wish
that the Boyle lecturers should, when "proveing the Christian
Religion against notorious Infidels (*viz*), Theists, Pagans,
Jews and Mahometans, not [descend] lower to any Controversies that are
among Christians
 themselves."[15]



Eventually, however, a furnace did arrive, and Boyle found himself
"so transported and bewitch'd [as to] fancy my Laboratory
a kind of Elysium ... . I there forget my Standish and my Bookes
and allmost all things" (Boyle to Katherine Ranelagh, Aug 31,
1649, BC 1:83).



Boyle was never a student at a university. Nor was he ever a fellow of
an Oxford College, though that too has been claimed on his behalf
(Dutton 1951, 20), but it was to Oxford that he removed after his time
at Stalbridge, and it was there that his interest in natural
philosophy flowered. Before taking up residence in Oxford however he
paid two lengthy visits to Ireland during the early 50s (for a year
from June 1652, and then for eight months from Oct 1653), and it was
from that "illiterate country" that he wrote to Clodius,
probably toward the end of his second Irish visit, in the spring of
1654:



> 
> For my part, that I may not live wholly useless, or altogether a
> stranger in the study of nature, since I want glasses and furnaces to
> make a chemical analysis of inanimate bodies, I am exercising myself
> in making anatomical dissections of living animals: wherein (being
> assisted by your father-in-law's friend Dr *Petty*, our
> general's physician) I have satisfied myself of the circulation
> of the blood, and the (freshly discovered and hardly discoverable)
> receptaculum chyli, made by the confluence of the venae
>  lactae;[16]
>  and have seen (especially in the dissections of fishes) more of the
> variety and contrivances of nature, and the majesty and wisdom of her
> author, than all the books I ever read in my life could give me
> convincing notions of (BC 1:167).
> 



It was also during this period, no doubt in large part due to
Cromwell's extremely harsh treatment of the Irish, that
Boyle's Irish properties were made secure and began returning
rents to him, ultimately reaching almost PS3000 p.a., Hooke told
Aubrey. The fact that Boyle's friend Petty conducted the survey
on which the disposal of the lands was based can hardly have been to
Boyle's disadvantage.



On October 12, 1655, Katherine was in Oxford investigating the
suitability of possible lodgings for Boyle. He was to lodge with the
apothecary John Crosse, whom Birch felt worthy of mention because he
had "a great acquaintance with Dr. *John
 Fell*,"[17]
 and the question was, which was the best room for his purposes, and
how was it to be furnished?



> 
> My Brother,
>   
> 
> It has pleased god to bring us safe to oxford & I am lodged at Mr
> Crosses with designe to be able to give you from experience an
> accoumpt which is the warmest roome, & indeed I am satisfied with
> neither of them as to that poynt, because the doores are placed soe
> just by the Chimeys that if you have the benifit of the fier you must
> venture haveing the inconvenience of the wind, which yet may be helped
> in either by a folding skreen & then I think that which lookes
> into the garden wilbe the more Comfortable... (BC 1:193).
> 



The house in question stood on the site where the Shelley Memorial now
stands, and his two rooms there seem to have served Boyle admirably,
though he later set up a retreat at Stanton St John's, where he
could retire when the press of society grew too great in Oxford.



In Oxford Boyle's tremendous output of works in philosophy,
theology, and experimental philosophy began. It was here that he
published *New Experiments Physico-Mechanical, Touching the Spring
of Air and its Effects, Certain Physiological Essays, The Sceptical
Chymist, Some Considerations touching the Usefulness of Experimental
Natural Philosophy*, and a number of others including *The
Origine of Forms and Qualities.*



Boyle's years in London (from 1668 to his death) saw the
continuation of his experimental work, along with a number of works on
philosophy and theology, including *The Excellency of Theology,
Compar'd with Natural Philosophy*, *Considerations About
the Excellency and Grounds of the Mechanical Hypothesis*, the
*Free Enquiry into the Vulgarly Receiv'd Notion of
Nature*, the *Discourse of things above Reason, Disquisition
about the Final Causes of Natural Things*, and *The Christian
Virtuoso*.



In 1691 Katherine died, and Boyle, whose health throughout his life
had been poor, died the following week.


## 2. Religious Views



The seventeenth century is notable not only for the number but also
for the variety of arguments which were offered to prove God's
existence. Although writers such as Pascal and Bayle felt such
arguments to be both unnecessary and unavailable, demonstrations of
God's existence were felt by many to be not only possible but
desirable, since they were necessary in the fight against
 atheism.[18]
 Descartes, as is well known, felt that God's existence could
be, and epistemologically had to be, demonstrated, and offered a
variety of proofs to provide such a demonstration. His version of the
ontological argument, his proof from the supposed innate idea of God,
his proof from the need for an eternal conscious
 being,[19]
 and his proof from the need for continuing creation, all found
supporters in the later seventeenth century, though the first two were
generally held to be unlikely to convince anyone.


### 2.1 Boyle on arguments for the existence of God



Apart from a brief reference to it in the printed works Boyle does not
mention the ontological argument (BW 9:413; Boyle 1772,
4:461-2). This distancing was not uncommon at the time. Ralph
Cudworth, though clearly fascinated by the ontological argument,
recognized that most would "Distrust, the *Firmness* and
*Solidity* of such *thin* and *Subtle*
*Cobwebs*," and offered an alternative argument in the
hope that it would prove more "Convictive of the
*Existence* of a God to the Generality" (Cudworth 1678,
725).



The language of the ontological argument was acceptable, even when the
argument's validity was rejected. Gassendi, for example, agreed
that God is that than which nothing greater can be conceived, but
denied the validity of the argument which offers this as its main
premise (See further Osler 1994, ch. 2). Nor was the argument from
innate ideas more popular. After his dialogue character Cuphophron has
espoused it, Henry More has his down to earth Hylobares burst out:



> 
> Well, *Cuphophron*, you may hug your self in your high
> *Metaphysicall* *Acropolis* as much as you will, and
> deem those Arguments fetched from the frame of Nature mean and
> popular: but for my part, I look upon them as the most sound and solid
> Philosophicall Arguments that are for the proving the Existence of a
> God (More 1668,
>  53).[20]
> 



Boyle, too, held that design arguments were both available and the
most likely to persuade rational, open-minded hearers. Such arguments
were intended to form a large part of a book on atheism, something he
worked on throughout his adult life but never published, though parts
of it were used in various other works of a theological
 nature.[21]
 Boyle did, however, leave a plan of the intended work, and in the
manuscript remains -- seven volumes of correspondence, forty-six
volumes of miscellaneous papers and eighteen volumes of notebooks
-- there are still a number of unpublished fragments and some
longer selections which he intended for this work.



Boyle intended "the little Tract about Atheism" to have
three sections:



> 
> 
> In the First of these, the Author represents some Reasons why it
> should not be thought strange if it be found somewhat difficult to
> demonstrate the Existence of a Deity.
> 
> 
> 1. The First of these Reasons is, that by reason of the selfe
> existence and Primity of God, his Essence cannot be Causable.
> 2. The Vitious Affections & Habits and the depravd frame of mind
> to be met with in most Atheists do very much indispose them to be
> convinc'd by the proofes of a Deity that might other wise be
> sufficient.
> 3. Since God is a Being whose Nature is the most singular of all,
> there must necessarily belong to him divers things, not to be
> paralleld.
> 4. The Difficulty of such speculations as belong to the
> Contemplations of Gods Attributes keeps the generality of Atheists
> & Libertines from being qualifyed for such Enquiries.
> 
> 
> 



In the second section <the Author> haveing premisd, that the
foregoing Reasons make it Equitable not to expect metaphysical or
rigid Demonstrations of a Deity, but to be content with a moral one,
if no better can be had, proceeds to the mediums whereof such a
Demonstration can be made up. Such as are



> 
> The innate Idea of a Deity
> 
> 
> The general Consent of mankind. (To one of which or both may be
> referrd the Epicurean Anticipation.)
> 
> 
> 
> The Reproaches or Boadings & Disquieting Terrors of a Guilty
> Conscience
> 
> 
> 
> The Fabrick & Conservation of the world, especially of Animals
> 
> 
> 
> The Nature & Propertys of the Soul of Man
> 
> 
> 
> The Lawes of its Union with the
>  Body[22]
> 
> 
> 
> The Universal Providence that directs the Affairs of Mankind.
> 
> 
> 
> Supernatural Effects whether of good or Evil Spirits (as their
> Apparitions Action Oracles Predictions &c)
> 
> 
> 
> The Patefactions that God has made of himselfe by true miracles. (To
> which Prophecies are reduc'd.)
> 
> 
> 



The Third section is spent in shewing some of the Reasons why the
Arguments proposd in the Second are often unprevalent.


1. And among the Intellectual Impediments the First is, That Atheists
often injuriously attribute to the notion of a Deity the fond Opinions
or rash Assertions of unskillfull men.
2. Atheists on the other side do sometimes no less injuriously father
their owne Errors & mistakes on the notion of a Deity.
3. They do not equitably consider the Nature of the Thing to be
proved, & the necessity that thence arises, that the Theory of the
Divine Attributes should be lyable to specious Objections.
4. They do not duely consider, that their owne Hypothesis is lyable
to some of the same difficulties & Objections, and to others that
they cannot solve.
5. The Objections are more popular & easy that are to be made
against the notion of a Deity than the Answers to those Objections
& the Arguments which prove that Notion.



Well, that was the plan, and Boyle certainly thought that the design
arguments he intended for section two should convince the open-minded.
Moreover, he thought, such arguments should particularly convince
those who were knowledgeable about nature, who knew enough about the
*details* of the world to be impressed by the intricacy of the
presumed workmanship. "[T]here are," he wrote,
"positive Reasons afforded by Philosophy to prove a Deity,
namely ... the Cartesian Idaea, the Originall of Motion, the
use of Parts in Animalls, especially the Eye, the valves of the heart,
the musculi perforantes &
 perforati,[23]
 & the temporary
 [parts][24]
 of a foetus <& the Mother>."



The argument from design, said Kant, "always deserves to be
mentioned with respect. It is the oldest, the clearest, and the most
accordant with the common reason of mankind" (Kant 1781,
A623/B651). But, he pointed out, there was a problem with it, a
problem which in fact had already been pointed not only by David
 Hume,[25]
 but by Boyle's younger contemporary, Charles Blount, who
wrote,



> 
> could we conclude any thing from *Miracles*, yet we could never
> thence conclude of the *Existence* of God. For since a Miracle
> is Work *limited*, and never implies any but a certain and
> limited Power: most certain and evident it is, that from such an
> Effect we cannot rightly infer the Existence of a Cause whose Power is
> *infinite*, but at most of a Cause whose Power is greater: I
> say, *at most*; because from many Causes concurring there may
> follow some Work, whose Force and Power is indeed less than the Power
> of all its Causes put together, but far greater than the Power of any
> one of them taken singularly (Blount 1683, 11).
> 



To a large extent Boyle accepted these points. He notes explicitly
that none of the proofs he was prepared to offer amounted to a
*demonstration* of God's existence, and indeed he felt
that a *demonstration* was not possible. A
*demonstration* was typically held to proceed from necessarily
true premises (often Aristotelian
 *principles*[26])
 via a valid argument to a necessarily true conclusion, and part of
what was at issue was whether we should be looking for a demonstration
of God's existence, or something less which would nonetheless
still be useful in the fight against atheism . "To haue the
Science of a thing," said Pierre du Moulin the elder, "two
certainties are required. The one is, that the thing be certaine of it
selfe and unchangeable. The second is, that the perswasion which wee
haue of it be firme and cleare" (Du Moulin 1624, 162). Gassendi
agreed, as did Arnauld and Nicole in the Port Royal Logic (Gassendi
1658, Canon XVI, 144; Arnauld 1662, part IV, ch 8, 323-4,
pagination as in the 5th, 1683 edition).



The persuasive alternative to a demonstration was sometimes styled a
*proof*, but often people spoke of *moral*
demonstrations as opposed to strict, or mathematical, demonstrations.
Boyle wrote:



> 
> besides the Demonstrations wont to be treated of in vulgar Logick,
> there are among Philosophers three distinct, whether *kinds* or
> *degrees*, of Demonstration. For there is a
> *Metaphysical* Demonstration, as we may call that, where the
> Conclusion is manifestly built on those general Metaphysical Axioms,
> that can never be other than true; such as *Nihil potest simul esse
> & non esse ... &c.* (Nothing can both be and not be
> at the same time) There are also *Physical* Demonstrations,
> where the Conclusion is evidently deduc'd from Physical
> Principles; such as ... *Ex nihilo nihil fit ...
> &c.* (From nothing, nothing comes) which are not so absolutely
> certain as the former, because, if there be a God, He may (at least
> for ought we know) be able to create & annihilate Substances
> .... And lastly, there are *Moral* Demonstrations ...
> where the Conclusion is built, either upon some one *such*
> proof cogent in its kind, or some concurrence of Probabilities, that
> it cannot but be allowed, supposing the truth of the most
> receiv'd Rules of Prudence and Principles of Practical
> Philosophy.
> 
> 
> And this *third* kind of Probation, though it come behind the
> two others in certainty, yet it is the surest guide, which the
> *Actions of Men*, though not their *Contemplations*,
> have regularly allow'd them to follow (BW, 8:281; Boyle 1772,
> 4:182-3).
> 
> 
> 



This moral certainty, Locke remarked, "is not only as great as
our frame can attain to, but as our Condition needs" (Locke
1690, 4.11.8).



When we look in detail at Boyle's discussions of the various
moral demonstrations outlined in his proposed second section it
becomes clear that he fancied some considerably more than others. He
often mentions the importance of conscience, but concentrates, as far
as proofs go, on various design arguments, on arguments based on the
incorporeality of the human soul, and on arguments involving miracles.
Unlike the clerical authors of the time he pays little or no attention
to the arguments from "the innate Idea of the Deity," from
"the general Consent of Mankind," or from "the
Universal Providence that directs the Affairs of Mankind."



Boyle did not expect his (or anyone's) proofs to convince most
atheists:



> 
> you need not thinke it strange, that I never pretended to convert
> resolved Atheists. For, besides the difficulty of treating clearly and
> cogently of such abstruse subjects as are many that relate to Atheism;
> the Will and Affections have so great an influence upon some mens
> Understandings, that 'tis almost as difficult to make them
> *beleive*, as to make them *Love*, against their Will.
> And it must be a very dazzleing Light, that makes an impression upon
> those that obstinately shut their Eyes against it. 'Tis not by
> Gods ordinary workes, but by his Extraordinary Power, that such men
> must be reclaimd to an acknowledgement of his <Existence>. For
> they that would find the Truth, especially in matters of Religion,
> must be diligent Inquirers after it, and *may be* strict
> Examiners of it, but *must not be*resolved Enemies to it. For
> to such, if to any, God is a Sun, that is not to be discover'd
> but by <his> owne Light (BP 2:64, BOA SS4.6.9 , p 384).
> 


### 2.2 Miracles



Boyle was aware that most believers held their belief on insufficient
grounds (see BP 4:60, BOA SS3.7.5, pp. 301-2), but felt
himself fortunate in that sound philosophy showed that the religion to
which he was born was the correct one. For Boyle, miracles (in
particular the miracle of Pentecost) were a crucial factor in opting
for Christianity. The Christian miracles, he felt, clearly bore the
stamp of God upon them. There were, he agreed, other miracles or
apparent miracles, but the miracles which purported to establish
Christianity were neither false nor diabolical, and they *were*
miraculous. Locke believed that "Mahomet having none to produce,
pretends to no miracles for the vouching of his mission," but
Boyle was aware of the argument that the *Koran* itself is
miraculous (in view of the disparity between it and what might
reasonably be expected of its author in the absence of divine
inspiration). He felt, not that this argument was inappropriate, but
that it failed the test empirically:



> 
> [T]he *Saracens*, press'd with their Religions being
> destitute of attesting Miracles, ... reply, That though there
> were no other Miracle to manifest the Excellency of their Religion
> ..., yet the Alcoran it Self were sufficient, as being a Lasting
> Miracle that transcends all other Miracles. How Charming its Eloquence
> may be in its Original, I confesse my self too unskilfull in the
> Arabick Tongue, to be a competent Judge ... but the Recent
> Translations I have seen of it in French, and ... Latin,
> elaborated by great Scholars, and accurate Arabicians, by making it
> very Conformable to its Eastern Original, have not so rendred it, but
> that Persons that judge of Rhetorick by the Rules of it current in
> these Western Parts of the World, would instead of extolling it for
> the Superlative, not allow it the Positive Degree of Eloquence; [and]
> would think the Style as destitute of Graces, as the Theology of Truth
>  ....[27]
> 



Boyle does not deny that the style could have been miraculous, and
indeed he runs a formally similar argument concerning the Apostles and
the miracle of Pentecost: the Apostles' "Hearers ...
knew it was <not> naturally possible, that uninspir'd
Persons, and especially illiterate Fishermen, should <grow>
able, in a trice, to make <weighty> discourses to many differing
Nations, in their respective Languages" (BP 7:99, BOA
SS3.6.29, p. 390). Boyle accepts, and indeed uses, the
*form* of the Koran argument: it is the premise he
disputes.



Boyle is ambivalent about the function of miracles. Generally he
regards them as being philosophically relevant after we have a proof
of God's existence, something which natural theology will afford
us. (Boyle fastens on two main types of design arguments: those
involving the complexity of animate beings, particularly very small
animate
 beings,[28]
 and those which highlight the need to explain the origin and
continuing function of natural laws: God must not only sustain
God's creatures, Boyle argues, he must also sustain the
regularities which we recognize as lawlike.)



Having convinced ourselves of God's existence through the
considerations which natural theology makes available to us, and
realizing that God is likely to institute a religion to make his
nature and requirements known to us, we look to miracles to see which
instituted religion is the correct one. However, though in general
Boyle argues that accepting something as a miracle
*presupposes* God's existence, and so miracles are to be
used to *institute* the correct religion rather than to ground
its metaphysical basis, he does sometimes urge an argument from
miracles which will yield not merely the correctness of Christianity,
but the acceptability of religious belief as such. Briefly: we have
good historical testimony for the occurrence of miracles, but miracles
are possible only if God intervenes in nature (and thereby exists) (BP
5:106-7, BOA SS3.8.3, pp. 310-12).


## 3. Boyle's World View


### 3.1 The creation of the world



Boyle had a straightforward notion of creation. First of all God, at a
particular, fairly recent, point in absolute time, made matter. Boyle
was an admirer of "our *Irish* St.
*Austin*"(BC 1:40), James Ussher, archbishop of Armagh,
who famously propounded what seems to us, though not to his
contemporaries, to be a very late date (4004 b.c.) for creation. Boyle
saw "no just reason to embrace their opinion, that would so turn
the two first chapters of *Genesis*, into an allegory, as to
overthrow the literal and historical sense of them" and, noting
the implausibility of the claims of "some extravagant ambitious
People, such as those fabulous *Chaldeans*, whose fond account
reach'd up to 40000 or 50000 years," held that
"Theology teaches us, that the World is very far from being so
old by 30 or 40 thousand years as they ... have presum'd:
and does, from the Scripture, give us such an account of the age of
the World, that it has set us certain Limits, within which so long a
Duration may be bounded, without mistaking in our Reckoning. Whereas
Philosophy leaves us to the vastness of Indeterminate Duration,
without any certain Limits at all" (BW, 8:21; Birch 1772,
IV:11). Revelation gives us (1) truths of which we would otherwise be
ignorant, such as "the order and time of the Creation of the
World and of the first man and woman"; (2) details of truths
which we can otherwise obtain "but very dimly, incogently, and
defectively"



> 
> such as ... That the World had a beginning, that 'tis
> upheld and govern'd by Gods general concourse & providence;
> that God has a peculiar regard to mankind; and a propitious one to
> good men; that he foresees those future things, we call
> *contingent*: that mens souls shall not dye with their bodyes,
> and many other articles of the Philosophers, as well as the Christians
> Creed (BP 7:242, 4:10-12, BW 14:268-9).
> 



Additionally there are (3) "*hints*" which lead us
to truths we would otherwise miss, such as "that whatever men
have generally believ'd, Vegetables had their Origine
independent from the Sun, the earth having producd all kinds of plants
a day before God made that Luminary" (BP 7:243, 4:15, BW
14:271). Moreover,



> 
> it ought much to recommend many of the things that Revelation
> discovers to us, that they are congruous, and if I may so speak
> Symmetrical to what reason it self teaches us; and this Supernatural
> Light does not only confirm, but advance and compleat the truths
> discoverable by the light of nature. For God has so excellently orderd
> the discoverys he makes of Theological <Veritys> by meer reason,
> and by the holy Scriptures, that what Revelation superadds to Reason,
> does both very well agree with it, and supply what was wanting to it,
> that from them both might result as compleat a body of Theological
> Verities, as is either necessary or fit for us in our Mortal State (BP
> 7:245-6, 4:23, BW 14:275). (See further MacIntosh 1992.)
> 



Unsurprisingly, then, Boyle makes a point of attempting to bring his
creation story into line with a literal interpretation of the Genesis
story. God, he believes, could have started things off earlier or
later, but chose not to. Having created matter, he broke it up and
started it moving. Sometimes Boyle says he broke it up *by*
starting it
 moving.[29]
*Then* he gave it laws, since the "casual justlings of
atoms" would not, Boyle thinks, have given rise to this
 world.[30]
 Hooke, explicating Genesis, argued for the same ordering. For Boyle
and Hooke, that is, a world without laws is not only possible, our
world was such a world for a time. In the previous century Konrad
Daspodius held that comets "drift without laws," but by
1686 Leibniz was writing, "God does nothing out of order, and it
is impossible even to feign events which are not
 regular."[31]
 Leibniz's point was that just as any 'random'
sequence of points will determine a curve (actually an infinite set of
curves, but Leibniz only needed the lesser claim), so any sequence of
events will conform to a regular pattern. Generalizing, we might say
that just as points underdetermine equations, so facts underdetermine
theories.



It should be noted however that for Leibniz, as for a number of his
contemporaries, not all such laws need be laws of
 *nature*.[32]
 Malebranche, for example, in his *Dialogues on Metaphysics*,
offered no fewer than five distinct types of law: "general laws
of the communication of motion, ... laws of the union of soul and
body, ... laws of the union of the soul with God, with the
intelligible substance of universal Reason, ... general laws
which give good and bad Angels power over bodies, ... finally,
the laws by which Jesus Christ received sovereign power in Heaven and
on earth, over minds as well as bodies, not only to distribute
temporal goods ... but to diffuse (*repandre*)
internal grace in our hearts" (Entretiens sur la
Metaphysique, in Malebranche 1962,
 12:319-320).[33]



Boyle's position is an intermediate one between the claim that
some objects or events are lawless, and the claim that lawlessness is
impossible. For Boyle, physical objects do exhibit nomological
regularities, but this is a contingent fact about the world, or
rather, for Boyle was cautious about generalizing, about the
spatio-temporal portion of it we occupy. He agrees, however, that
there are laws that are *not* laws of nature, with the laws of
interconnection between body and soul providing, for him, an obvious
example. This interconnection also provides a clear example of a state
which God constantly preserves.



After having made matter, started it moving, and given it laws, God
then formed the matter into particular structures and shapes,
including certain "seeds." Then he added some
"seminal principles" with formative plastic powers. Boyle
does not clearly indicate whether or not these are a special subclass
of natural laws affecting matter, or whether they are in some way what
he sometimes calls "supra-mechanical," though he does
point out that if there is a mechanism for animal inheritance, then it
would seem to require a framing intelligent agent (BW, 12:445-6,
Birch 1772, VI:728-9. See Anstey 2002a and Inglehart 2015 for a
full discussion of the issue.). His older contemporary Harvey, much
admired by Boyle, was in no doubt about the matter, pouring scorn on
those who talk



> 
> As if (forsooth) *Generation* were nothing in the world but a
> meer Separation, or Collection, or Order of things. I do not indeed
> deny that to the Production of one thing out of another, these
> fore-mentioned things are requisite, but *Generation* her self
> is a thing quite distinct from them all ... (Harvey 1653, 51).
> 



All this holds for the corporeal universe, as opposed to the three
sorts of incorporeal creatures God created or, in our case, continues
to create: angels, evil demons, and human souls: the good, the bad,
and the
 imprisoned.[34]
 The angels were created "before the visible World ... was
half compleated," but God creates new human souls daily, and
moreover works a "physical miracle" to attach them to
their respective bodies (BP 7:243, 4:14, BW 14:271; BP
 2:62).[35]
 Sometimes Boyle felt that although humans are made in God's
image they, like other created beings, are "at their best but
umbratile, and Arbitrary Pictures of God their Creatour" (BP
4:4, BOA SS2.2.38, p. 145). Elsewhere, however, he offers a more
traditional account of the soul as the image of God:



> 
> The Christian virtuoso considers the rational soul, not barely as it
> guides the motions of that living engine, we call the body, but as it
> is a kind of imprisoned angel, that bears the image of God, and is
> capable of knowing, both ourselves and him; and by a consciousness of
> her being his production, is capable of acknowledgeing, loving, and
> obeying him, and referring to his glory all the excellencies she
> discovers, both in herself, and in the body she is united to; by which
> just reference, she is, by his goodness, in his divine Son, made
> capable of becoming incomparably more knowing, than here she is, and
> eternally happy with him (BW, 12:504, Birch 1772, VI:775).
> 



Although humans are made in the image of God, they are considerably
less clever than the
 angels,[36]
 and since it is quite possible that God's primary end in making
the universe was to provide a universe for the angels, and not
centrally for humans, it is thereby quite possible that the universe
will be too complicated for us to understand:



> 
> [I]f God be allowed to be, as indeed he is, the Author of the
> Universe, how will it appear that He, whose Knowledge infinitely
> transcends ours, and who may be suppos'd to operate according to
> the Dictates of his own immense Wisdom, should, in his Creating of
> things, have respect to the measure and ease of Humane Understandings;
> and not rather, if of any, of Angelical Intellects? So that whether it
> be to God or to Chance, that we ascribe the Production of things, that
> way may often be fittest or likelyest for Nature to work by, which is
> not easiest for us to understand (BW, 3:257, Birch 1772, II:46).
> 



"[W]e presume too much of our own abilities," Boyle wrote,
c. 1680, "if we imagine that the omniscient God can have no
other Ends in the framing & managing of Things Corporeal, than
such as we Men can discover" (Boyle MS 198, fol. 120, BP 7:116,
BOA SS3.6.3, p 267). It follows at once that while simplicity may
often be our best guide as to what working hypothesis to choose, we
should not think it to be inevitably a reliable guide to truth.



Why did God create the universe in this piecemeal way? What is
Boyle's rationale for thinking that God didn't just start
off by creating matter in motion with the proper directed velocities
and letting it give rise to the present world in its own good time? Or
why not suppose that he created the *present* world as a going
concern? Boyle doesn't tell us, but two points stand out.



First of all, it certainly fits the fact that Boyle has a very limited
view of
 omnipotence.[37]
 Here he is, for example, bemused by the swiftness of God's
creative ability:



> 
> As great a Number & variety of parts as a living Humane Body
> consists of, 'tis highly probable that the Lump of
>  Stupid[38]
>  matter out of which they were fashion'd, was contriv'd
> into this admirable System; if not in a moment, yet in a very short
> time. For the sacred story relates, that man was not created till
> <about> the end of the six dayes work; and since in One day God
> created all the four footed Beasts, (wilde & tame,) and all the
> numerous Reptiles that creep upon the Earth after their kind;
> 'tis no way improbable that among so great a multitude of
> differing *species* of Animals, or Living Engines, that were
> made in one Part of the same sixth day, God should make a Humane
> Animal in an extreamly short time, not to say *in a trice* (BP
> 4:85, BOA SS2.2.68, p 161). [Here and throughout in quotations,
> the emphasis is in the original.]
> 



Doing things step by step, fairly quickly, and with moderate success,
was quite enough to excite Boyle's admiration for the Almighty
and, though he had certainly read Descartes's
*Principles* (in which Descartes remarks explicitly that
although God *could* have let things work their way from a very
different initial state to the present world, *in fact* God
started the world off *in medias res*), it is quite possible
that the alternative did not strike him as likely: he was not, after
all, a mathematician, or even a mathematical
 physicist.[39]



Given this, and the fact that motion was not natural to matter, but
had to be added to it, it would seem plausible to Boyle that God
created matter first, and then gave it a push, particularly since the
push had to be precisely fine tuned in order to yield just the world
we now have. (That matter is not naturally in motion forms the basis
of one of Boyle's criticisms of Epicurus. Boyle takes Epicurus
to hold that motion *is* an innate property of matter. How
then, asks Boyle, are we to explain the fact that it is lost or
changed as a result of collision between particles? (BP 2:5, BOA
SS4.1, p 340).) Additionally, Boyle notices that no system of laws
can offer a complete explanation: we also need an account of the
initial
 parameters.[40]
 But then, since they are logically distinct, why not have them
chronologically distinct as well?



Secondly, there are, perhaps, historical reasons. For Boyle is
conscious of himself as building on past views, and such views
typically treated matter as giving rise to the present world, and, in
the case of some past thinkers, at least, as having existed in a
constant state for some time before the initiating changes that led to
the present world occurred. The notion of a piecemeal creation, that
is, fits Boyle's views of God's abilities, fits
*Genesis*, and fits the views of previous thinkers. Probably we
do not need to look farther for an explanation for his adopting such a
view.


### 3.2 What kind of world is it that God created?



God created a material world in time and space, but what kind of
matter, what kind of space, what kind of time? As to the matter, Boyle
agreed with contemporaries such as Huygens and Newton that
"Matter [is] in its own Nature but
 one."[41]
 However Boyle, cautious as ever, explicitly allows God the
possibility of creating matter which is *not* like ordinary
matter, and instituting laws which are quite unlike the laws that
obtain on earth. His views are worth quoting at length:



> 
> 
> [T]he World must every way have bounds, and consequently be finite; or
> it must not have bounds, and so be ... *infinite*. And if
> the World be bounded, then those that believe a
>  Deity,[42]
>  to whose Nature it belongs to be of infinite Power, must not deny
> that God was, and still
>  is,[43]
>  able to make other Worlds than this of ours. ...
> 
> 
> 
> Now if we grant, with some modern Philosophers, that God has made
> other Worlds besides this of ours, it will be highly probable that he
> has there display'd His manifold Wisdom, in productions very
> differing from those wherein we here admire it. And even without
> supposing any more than one Universe, as all that portion of it that
> is visible to us, makes but a part of that vastly extended aggregate
> of bodies: So if we but suppose, that some of the Celestial Globes,
> whether visible to us, or plac'd beyond the reach of our sight,
> are peculiar Systemes, the consideration will not be very different.
> For since the fix'd stars are many of them incomparably more
> remote than the Planets, 'tis not absurd to suppose that as the
> Sun, who is the fix'd star nearest to us, has a whole Systeme of
> Planets that move about him, so some of the other fix'd Stars
> may be each of them the Centre, as it were, of another Systeme of
> Celestial Globes ... . Now, in case there be other Mundane
> Systemes (if I may so speak) besides this visible one of ours, I think
> it may be probably suppos'd that God may have given peculiar and
> admirable instances of His inexhausted Wisedom in the Contrivance and
> Government of Systemes, that for aught we know may be fram'd and
> manag'd in a manner quite differing, from what is observ'd
> in that part of the Universe that is known to us. ... [H]ere on
> Earth the Loadstone is a Mineral so differing in divers affections,
> not onely from all other Stones, but from all other bodies, that are
> not Magnetical, that this
>  Heteroclite[44]
>  Mineral scarce seems to be Originary of this World of ours, but to
> have come into it, by a remove from some other World or Systeme
> ....
> 
> 
> 
> Now in these other Worlds, *besides* that we may suppose that
> the Original Fabrick ... into which the Omniscient Architect at
> first contriv'd the parts of their matter, was very differing
> from the structure of our Systeme; *besides* this, I say, we
> may conceive that there may be a vast difference betwixt the
> subsequent *Phaenomena*, and productions observable in one
> of *those* Systemes, from what regularly happens in
> *ours*, though we should suppose no more, than that two or
> three Laws of Local Motion may be differing in those unknown Worlds,
> from the Laws that obtain in ours (BW, 10:172-3, Birch 1772,
> V:138-139).
> 
> 
> 



Boyle, that is, sees three distinct possibilities: the initial set up
may differ, the matter involved may differ, and the laws in question
may differ. Moreover the laws, as well as the matter, could have been
formed differently by God, and could indeed vary from part to part of
the current universe *within* the universe. Clearly the case of
varying laws and the case of varying matter may run into each other,
but Boyle treats them as distinct possibilities, and gives as an
example the possibility of a combination of conservation and
non-conservation possibilities: we can envisage bodies with the
"power of exciting Motion in another Body, without the Movents
loosing its own." Were this to be the case the resulting
phenomena would be "strangely diversifyed." Moreover, God
may have made a universe, or a part of this universe, which was such
that "*some* parts of matter [would] be of themselves
*quiescent* ... and determin'd to continue at rest
till some outward Agent force it into motion [while] *other*
parts of the matter [may have] a Power ... of restlessly moving
themselves, without loosing that power by the motion they excite in
quiescent bodies. ... Nor is it so extravagant a thing, as at
first it may seem, to entertain such suspicions as these. For in the
common Philosophy, besides that the Notion and Theory of Local Motion
are but very imperfectly propos'd, there are Laws or Rules of it
not *well*, not to *say at all*,
 establish'd."[45]



Boyle does not use the terminology of absolute space and time, but he
remarks that God could have made the world earlier:



> 
> Nor was it his Indigence, that forc't him to make the World,
> thereby to make new Acquisitions, but his Goodnesse, that prest him to
> manifest, and to impart his Glory; and the goods, which he so
> over-flowingly abounds with. Witness his Suspension of the
> World's Creation, which certainly had had an earlier Date, were
> the Deity capable of Want, and the Creatures of Supplying it (BW,
> 1:97, Birch 1772, I:270).
> 



Boyle's general view about both space and time is that since
they are



> 
> Primary & Heteroclite ... 'tis noe wonder that our
> Limited & Imperfect understandings should not be able to reach to
> a full & clear comprehension of them, but should be swallowd up
> with the <Scruples &> Difficulties that may be suggested by
> a <bold &> nice Inquiry into things, <to> which there
> seemes to belong a kind of Infinity (BP 2:53).
> 



He also remarks about the world that



> 
> *if* it be Finite [which Boyle allows as a possibility], then
> 'tis not in a place (such as the Schools define) after the
> manner of other Bodys, since there is no ambient Body whose inward
> surface determines it; and we may conceive it to move several wayes,
> as upwards or downwards, and yet not to change place, because (as was
> just now said,) it is in none, and all its Extream parts may keep the
> same situation in reference to one another (BP
>  1:64).[46]
> 



Moreover, there is a



> 
> rigid and Philosophical Notion ... of rest, which for distinction
> sake may be called Absolute or Perfect Rest; which imports a
> continuance of a Body in the same place *precisely*, and
> includes an absolute Negation of all local Motion, though never so
> slow or imperceptible; ... in this rigid sense of the word Rest,
> I durst not affirm, that there are any Bodies at Rest in the Universe
> (at least for any long time) but willingly [allow] it to be made a
> Problem, whether there be any or no; ... perhaps I [incline] to
> the Negative part of the Question (BW, 6:194, Birch 1772,
>  I:444).[47]
> 



Again, Boyle writes: "Suppose a Ball were in motion, & all
the world should be on a sudden annihilated about it; why may not the
motion of that Ball be continu'd? there being nothing to stop
it; & if it be continu'd, we have a motion where the mobile
dos not quitt the neighborhood of som bodys, and approach nearer to
others" (BP 1:3).



We have, then, Boyle's view that a body can continue "in
the same place *precisely*," that the whole (finite)
universe might move in space, and that God could have created the
world earlier than he did. Such views do not at least amount to a
*rejection* of absolute space and time. Boyle's
contemporary, Leibniz, who did reject absolute space, explicitly drew
the conclusion that a finite universe could *not* move as a
whole in space, and could *not* have been created earlier in
 time.[48]



The universe God created, then, contains a number of finite
*incorporeal* entities, for whom the writ of physics does not
run, and a number of material entities, compounded as far as we are
aware, of the same matter in every case, set in a space and time
independent of them, and subject to a number of God given laws.


### 3.3 Final causes



As for teleology, Boyle wrote an influential treatise entitled *A
Disquisition about the Final Causes of Natural Things* which
appeared in 1686. In opposition to Epicurus, he argued that there are
final causes and in opposition to Descartes, he claimed that in many
cases we can have epistemic access to these final causes, though he
agreed that we ought not be presumptuous in these matters. According
to Boyle, there are four types of final cause that we can know. First,
there are the "grand and General Ends of the whole World, such
as the Exercising and Displaying the Creators immense Power
...." Second, are the ends in the nature and motions of the
celestial objects and the Earth. Third, there are the ends that
pertain to the parts of animals and fourth there are human ends (BW,
11:87). Boyle was quite adamant that there are no ends that pertain to
inanimate objects. In particular, he rejects any form of immanent
teleology in virtue of which material objects are able to direct their
behaviour: "For inanimate Agents act not by choice, but by a
necessary impulse, and not being endow'd with Understanding and
Will, cannot of themselves be able to moderate or to suspend their
actions" (BW, 4:267. See Carlin 2011, 2012, 2020).


## 4. Laws of Nature



On a number of occasions Boyle assures us that "God [is] the
Author of the universe & free Establisher of the Laws of motion,
whose generall Concourse is necessary to the conservation &
Efficacy of every particular Physicall Agent" (BP 2:132). The
trouble is, he seems to have thought that this remark was fairly
transparent, and does not trouble to explain it to us. Moreover, he
tends to use much the same phraseology on each occasion he discusses
the issue. It was a commonplace of the time that Boyle was no stylist
-- it was obvious at times to Boyle himself -- but though
even the obsequious Budgell remarked that Boyle was "too wordy
and prolix," in this case at least he was not wordy enough
(Budgell 1732, 124).



It is tempting to suppose that Boyle must have had some reasonably
well thought out views on the question of *how* God sustains
the world. He was after all one of the most impatient of thinkers when
it came to fake or non-explanations, and he was in general very aware
of the danger of letting verbal 'explanations' get in the
way of real ones. He objected against the scholastics, for example
that



> 
> to explicate a *Phaenomenon*, being to deduce it from
> something else in Nature more known to Us, than the thing to be
> explain'd by It, how can the imploying of Incomprehensible (or
> at least Uncomprehended) substantial Forms help Us to explain
> intelligibly This or That particular *Phaenomenon*? For to
> say, that such an Effect proceeds not from this or that Quality of the
> Agent, but from its substantial Form, is to take an easie way to
> resolve all difficulties in general, without rightly resolving any one
> in particular; and would make a rare Philosophy, if it were not far
> more easie than satisfactory ... (BW, 5:351-2, Birch 1772,
>  III:46-7).[49]
> 



On the other hand, in theology he was more likely than elsewhere to
let things get by, since he was convinced in advance that his
theological picture was the right one, and he was used to stifling
doubts about theological claims. Writing about himself in the third
person as a young man he speaks of the "fleeting Clouds"
of doubts which never ceased "now & then to darken /obscure/
the clearest serenity of his quiet: which made him often say that
Injections of this Nature were such a Disease to his Faith as the
Tooth-ach is to the Body; for tho it be not mortall, 'tis very
troublesome" (BP 37:182r). (These doubts persisted: see Hunter
1990, 410.)



Moreover, he had a well worked out doctrine concerning the limitations
of reason, and often points out that we should not expect fully to
understand God's workings, for God is, after all, "<a
Being> of a most Primary and most singular Nature" (BP 2:107,
2:37, BOA SS 4.1, p 357). (For different interpretations of Boyle
on the limits of reason see Wojcik 1997, Holden 2007 and Marko 2014.)
Furthermore, he was willing to admit the impossibility of our
understanding -- at least given the present limitations on our
intellects -- even quite ordinary and lawlike matters, e.g., the
way in which the human soul and human body interact. How God could
have created the world, and how it is that he can intervene in it, are
matters as mysterious to us as how mind and body can interact, and
that is a total mystery.



Sometimes, Boyle remarks, our ignorance of things has to do simply
with our lack of knowledge of the inner or hidden workings of a thing.
He offers his, and indeed the century's, standard example of
clocks which may have various internal mechanisms to produce the same
outer effects. Thus he remarks that "we know in general, that
digestion is made by some *Menstruum* or subtile substance in
the Stomach; tho we know not the particular nature of that
substance, (as whether it be Acid, Urinous, &c.)".
Sometimes, though, our ignorance is of a deeper, richer variety:



> 
> *sometimes* ... we are not able to conceive the
> *Modus* of a thing, soe much as *in general*, or, as to
> the *possibility* of it, (abstracting from the positive Proofs
> that such a thing is) as, when we cannot conceive, how the Rational
> Soul can stop or determine the motions of the <humane> Body. And
> in this latter case, our not knowing the *Modus* of a thing, is
> usually more than a bare Ignorance, and inclines us to frame
> Objections against the Truth or Existence of the thing: because
> oftentimes the Incomprehensiblenes of the *Modus*, is grounded
> upon some thing that we conceive to be in the case, repugnant to the
> Laws or Course of Nature, or to some Dictate of right Reason: as, in
> the instance newly mention'd, it seems repugnant to the nature
> of things, that an Immaterial substance, not being Impenetrable, can
> resist or reflect the motion of a Body &c (BP 1:129, 7:155v, BOA
> SS3.5.19, p 255).
> 



Boyle was impatient with the Cartesian suggestion that we might be
able to alter the direction though not the quantity of motion, not for
Leibniz's reason that the notion of quantity of motion required
a confusion between momentum and kinetic
 energy,[50]
 but for the straightforward reason that interfering with the directed
velocity required as mysterious an interaction as altering the
'quantity of motion' would. He was aware of the Cartesian
claim "that the rational Soul doth [not] give any motion to the
parts of the Body, but only *guide* or *regulate* that
which she finds in them already" (BW, 9:379, Birch 1772,
IV:416), but that, he felt, did not really solve the problem, for that
interaction was as mysterious as an energy introducing one: "I
do as little conceive how the motions of the *Conarion* can
work upon an Immaterial soul, as how any other part of the Body can do
it. Nor do I conceive how an Immaterial Soul can work upon the
*Conarion* its self, more then it can upon any other part of
the Body" (BP 1:128 BOA SS3.5.15, p 253), and he notes that
it will not "suffice to object, that the human will does, in
these cases, not produce any new motion, but only determine[s] the
motions of the spirits, and by their means of the locomotive organs.
For to put a check, at pleasure, to the motion of a body, that does
already actually move in one line, and determine its motion to
continue in another, that is perhaps differing from it, or even
opposite to it; to do this, I say, without opposing to the moving
body, some other body, which, by its resistance and situation may
change its former course, is not a mechanical operation" (BW,
12:480, Birch 1772, VI:756). A change of direction, just as much as a
change in the 'quantity of motion,' is in fact as
mysterious and inexplicable, if done by incorporeal means, as the
introduction of energy into the system would be.


## 5. Boyle's Law



Many of us learned at school that Boyle's Law holds for ideal
gases and can be summarized as \(PV = k,\) where \(k\) is a constant, and \(P\)
and \(V\) are pressure and volume respectively. This law does stem from
Boyle's work, but it is not what Boyle took himself to have
 demonstrated.[51]



Boyle was arguing specifically against a Jesuit scientist, Franciscus
Linus, who claimed, not that ordinary atmospheric air does not have
any pressure (a spring), but that its pressure was not sufficiently
powerful for it to do all the things it does in fact do. So Boyle
decided on an experiment to show the way in which, as we would say,
the pressure and the volume of the air vary, when the air is, in
Boyle's words, either 'compressed or dilated.'



He and his assistant, at the time Robert Hooke, made a J shaped tube
and began to make a few measurements, but "were hindered from
prosecuting the trial at that time by the casual breaking of the
tube."



Subsequently they made another, larger, better piece of apparatus, and
taking particular care that the measurements should be accurate,
tested the hypothesis "that supposes the pressures and
expansions to be in reciprocal proportion." The results are set
out, with misprints, in two tables, and Boyle's conclusion was
that the experimental findings matched the predicted results very well
in the case of compression, less well in the case of rarefaction.
Boyle suggested that the divergence from the expected result in the
case of rarefaction may have been due to "some little aerial
bubbles in the quicksilver" ("so easy is it in such nice
experiments to miss of exactness," he added).



Now, what did Boyle take himself to have shown? First, that there is,
as a matter of experimental fact, a spring to the air: this is not in
the sense in which Boyle understands the term, any longer an
hypothesis: it is now obvious from the experimental results: what
explains, or purports to explain this fact will be a theory or an
hypothesis, but the result itself is in no sense an hypothesis. As
Boyle said



> 
> ...to determine whether the motion of restitution in bodies
> proceed from this, that the parts of a body of a peculiar structure
> are put into motion by the bending of the spring, or from the
> endeavour of some subtle ambient body, whose passage may be opposed or
> obstructed, or else its pressure unequally resisted by reason of the
> new shape or magnitude, which the bending of a spring may give the
> pores of it seems to me a matter of more difficulty, than at first
> sight one would easily imagine it. Wherefore I shall decline meddling
> with a subject, which is much more hard to be explicated than
> necessary to be so by him, whose business it is not ... to assign
> the adequate cause of the spring of the air, but only to manifest,
> that the air hath a spring, and to relate some of its effects (BW,
> 1:166, Birch 1772, I:12).
> 



Secondly, Boyle takes himself to have shown that, for atmospheric air,
within the limits of his experimental set-up, "the pressures and
expansions [are] in reciprocal proportion," or, as we would say,
pressure and volume vary inversely. He doesn't take himself to
have shown anything more than this. He does remark that further
experiments may show that the relationship holds outside the boundary
conditions imposed by the experimental set-up, but the experiments he
has just made certainly don't show that. What Boyle expressly
said was,



> 
> till further trial hath more clearly informed me, I shall not venture
> to determine, whether or no the intimated theory will hold universally
> and precisely, either in condensation of air, or rarefaction: all that
> I shall now urge being, that...the trial already made
> sufficiently proves the main thing, for which I here allege it; since
> by it, it is evident, that as common air, when reduced to half its
> wonted extent, obtained near about twice as forcible a spring as it
> had before, so this thus comprest air being further thrust into half
> this narrow room, obtained thereby a spring about as strong again as
> that it last had, and consequently four times as strong as that of the
> common air (BW, 3:60, Birch 1772, I:159).
> 



Thus Boyle's Law, for Boyle, was not a universal generalization
about ideal gases: it was a strictly limited claim about common or
atmospheric air. Boyle did add that "there is no cause to doubt,
that if we had been here furnished with a greater quantity of
quicksilver and a very strong tube, we might, by a further compression
of the included air, have made it counter balance the pressure of a
far taller and heavier cylinder of mercury."



But he did not claim that the same ratio between pressure and volume
would hold in such more extreme cases. Nor did he claim that there are
no limits to the possible compression. It is worth stressing that
Boyle had this limited view of his result, for Shapin and Schaffer
1985 suggest that



> 
> The work Boyle undertook in reply to Linus was ... done ...
> with a specially constructed J-shaped tube in which pressures higher
> than atmospheric could be attained. Using this apparatus Boyle showed
> that if he compressed air twice as strongly as usual he could produce
> twice as strong a spring. He concluded that the process could go on
> indefinitely, so that there were no limits to the power of the
> air's spring (Shapin and Schaffer 1985, 168-9).
> 



But Boyle was quite happy not to draw such conclusions, simply because
his experiments didn't allow that kind of jump. There are other
important ways in which he thought that generalizations about nature
might fail of universality. He had a very healthy notion of the
complexity of the world, and an acute sense of the difficulties to
which even apparently simple experiments could give rise. In fact,
Boyle had was one of the first philosophers ever to develop a
philosophy of experiment.


## 6. Boyle's Philosophy of Experiment



Boyle was one of the first philosophers to develop a philosophy of
experiment. His view, which derived in part from Francis Bacon, has
many parallels with that of his fellow experimenter Robert Hooke and
this Bacon-Boyle-Hooke philosophy of experiment came to exert great
influence on the development of natural philosophy in the late
seventeenth century (Anstey 2014).



Boyle's view of experiment is best understood in the context of
the newly emerging experimental philosophy of the early Royal Society
of London in the early 1660s and its precursor groups in Oxford in the
late 1650s. At this time the discipline of natural philosophy was
shifting from being regarded as a speculative science, like, say,
theology, to being an operative or practical science in which
experiments played a central role.



The first tenet of Boyle's philosophy of experiment is that
observation and experiment should have epistemic priority over theory.
That is, one should accept only those principles and axioms in natural
philosophy that are based upon sufficient observational and
experimental evidence and one should avoid constructing a theory
without recourse to observation and experiment. Speculative philosophy
commences with principles that are accepted without recourse to
experiment, whereas experimental philosophy begins with observation
and experiment and only then proceeds to theory.



Secondly, Boyle believes that although one should not start
one's inquiries from untested principles, one can nevertheless
reason upon experiments:



> 
> Not that I at all disallow the use of Reasoning upon Experiments, or
> the endeavouring to discern as early as we can the Confederations, and
> Differences, and Tendencies of things: For such an absolute suspension
> of the exercise of Reasoning were exceedingly troublesome, if not
> impossible. (BW, 2:14)
> 



It is hardly surprising then to find that Boyle wrote quite
extensively on the relation between experimental philosophy and
speculative philosophy and on the usefulness of reason to the
experimental philosopher. For example, in a catalogue of his
unpublished works dating from 1684 there is listed a work entitled
"Of Usefulnes of Speculative & Experimental Philosophy to
one another" (BW, 14:342). Unhappily this work is no longer
extant.



Thirdly, according to Boyle, once a theory is constructed, the natural
philosopher should be prepared to revise it in the light of new
experimental evidence: "I would have such kind of
superstructures look'd upon only as temporary ones
..." (BW, 2:14). The only things that Boyle will remain
certain of are matters of fact: "I dare speak confidently and
positively of very few things, except Matters of Fact" (BW,
2:19).



Fourthly, while Boyle believed in ultimate causes underlying natural
phenomena, he also acquiesced in Bacon's conception of a scale
of causes and the need to discover intermediate causes *en
route* to ultimate explanations:



> 
> there are oftentimes so many subordinate Causes between particular
> Effects and the most General Causes of things, that there is left a
> large field wherein to exercise Mens Industry and Reason, if they will
> but solidly enough deduce the Properties of things from more general
> and familiar Qualities, and also intermediate Causes (if I may so call
> them) from one another. (BW, 2:23)
> 



One such intermediate cause that was of great importance for Boyle is
the spring (or pressure) of the air (see Anstey 2002b; Chalmers 2012).
Boyle was aware that this quality was not one of those causes
"that are the highest in the scale or series of Causes"
(BW, 2:21), and that he had to be content with its intermediate
status.



This cluster of doctrines about experiment was set in Boyle's
writings within a broader Baconian context, namely the Baconian method
of natural history. Baconian natural histories were, in the first
instance, vast collections of matters of fact derived from observation
and experiment and which were to provide the foundation for natural
philosophical theorising. (In fact, few natural philosophers were able
to respect this two-stage process.) They are to be distinguished from
classificatory natural history that was concerned with describing and
classifying natural kinds (Ogilvie 2006). Thus, many of Boyle's
actual experimental reports are found in works that are natural
histories after the style of Francis Bacon. For example, Boyle viewed
his famous air-pump experiments that led eventually to the discovery
of Boyle's Law, as part of a broader natural history of the air.
Indeed, the philosopher John Locke, who was also committed to the
Baconian method of natural history, edited Boyle's *General
History of the Air* and saw it through the press the year after
Boyle died.



There are two important implications for Boyle's philosophy of
experiment that derive from the natural historical context in which it
was set. First, it accounts for the fact that many of Boyle's
experiments were almost completely divorced from theory - they
were experiments that "had a life of their own," -
to use Ian Hacking's felicitous phrase (Hacking 1983, chapter
9). Secondly, the natural historical context helps to explain the very
rich typology of experiments that Boyle used. Boyle followed Bacon in
distinguishing between luciferous (light-bearing) experiments that
revealed underlying causes and fructiferous (fruit-bearing)
experiments, that produced useful knowledge and technologies. This
distinction was widely used in the seventeenth century. Another type
of experiment that derives from Bacon, was named by Boyle and was made
famous by Newton. This was the crucial experiment (*experimentum
crucis*) (BW, 3:50-1).



He also coined the term 'exploratory experiment' to
describe a form of experimentation that includes 'The devising
of New and convenient Tools or other Instruments for altering the
usual State or the common course of things, and for thereby reducing
nature to vary her Course and afford the Enquirers some new
Phaenomena' (BP, 9:52). This is clearly a precursor of the
modern notion of exploratory experiment (Steinle 2016).



Boyle was fully aware that some of the central tenets of his view of
experiments and his own natural historical methodology derived from
the writings of Francis Bacon. But he did not believe that Bacon was
the first to practise experimental philosophy. Interestingly, Boyle
believed that his approach to natural philosophy found precedents in
some of the presocratic philosophers, such as the Greek atomist
Democritus and the (shadowy) Phoenician Moschus whom he surmised were
experimental corpuscularians (Levitin 2014).


## 7. Perception and the Soul



Two distinct notions of the soul occupied centre stage in the
seventeenth century. One, stemming from Plato and the Pythagoreans,
with theological trimmings by Augustine, had been given immense
prestige by Descartes' championing of it. This view was what
Geach has called the "savage superstition ... that a man
consists of two pieces, body and soul, which come apart at
death." Geach adds, "the superstition is not mended but
rather aggravated by conceptual confusion, if the soul-piece is
supposed to be immaterial" (Geach 1969, 38).



The second main account, stemming from Aristotle, had been taken over
and made Christian by Thomas
 Aquinas.[52]
 In this account the soul was, though incorporeal, not simply a
separate bit attached to the body, but was the form of the individual
animal in question, whether human or not. Aquinas presented arguments
to show that human souls were subsistent in view of various capacities
they had, and proceeded from there to argue for the possibility of the
continuing existence of human souls in the absence of the body. He
was, however, clear that the human person (even when the person in
question was Christ in human form) was not merely a soul with an
attached body, but was the body informed by the soul: if your soul
alone were to survive death you would not. Bodily resurrection is
essential to the survival and immortality of humans.



Cartesians and Thomists alike believed on scriptural grounds that
there were actual cases of separated souls, namely, the angels, fallen
and unfallen, so the possibility that the human soul might itself be
subsistent was simply the possibility that it might sufficiently
resemble an already accepted ontological group: despite the problems
that substance dualism raises, a number of which presented themselves
clearly to Boyle, there was no *general* problem concerning
incorporeal entities, and there were, Boyle felt, strong arguments for
the incorporeality of the human soul.



For Boyle, as for other leading seventeenth century figures,
perception was a matter of information entering the brain as a result
of causal interaction between the perceiver and the perceived object.
Arriving at the brain the information was processed by a subsystem or
set of subsystems devoted to presenting it to the cognitive system,
and to storing it thereafter. The initial processing was done by a
system, the *common* sense, that combined the inputs from the
various sense organs (left eye + right eye; eyes + ears; etc.) and it
was then *imagined* -- that is, an image was formed in the
brain though, as Kepler and Descartes noted explicitly, the image was
not a literal, optical, image. That apart, seventeenth century
thinkers accepted in general outline the position which had already
been set out in the thirteenth century by Roger Bacon, who was in turn
simply collating the views of earlier Islamic writers on the subject,
though of course the details, particularly the details of the causal
interaction between percipient and perceived, varied from writer to
writer (See further Lindberg 1976, MacIntosh 1983, and Sutton
1998).



Imagination was a matter of material images being formed in the brain.
But, it was held by Boyle and others, we have knowledge of things
which are literally unimaginable -- that is, they cannot be
accurately represented by a corporeal image in the central nervous
system. There were a variety of reasons for this belief. First it was
held that there were things which were too large, and things which
were too small to be imagined, that is, imaged. Hence some
non-material faculty was needed to account for this ability.
Additionally, there are things which are not image-able because they
cannot be represented accurately by *any* physical system.
Boyle's stock example in this area, though not his only example,
is the incommensurability of the sides and diagonal of a square. Since
\(\sqrt{2}\) is irrational no discrete (corpuscular) system can accurately
represent both. But we do have knowledge of squares. Therefore we must
be employing a non-material system. Also, there were things such as
Descartes' chiliagon which, while they could be represented
physically, could not (as experience shows) be represented accurately
by *our* physical imaging system.



Additionally (a familiar Aristotelian point), our ability to abstract
-- to consider universals and not merely particular instances
-- was held to provide further evidence for the incorporeality of
the soul and hence for the possibility at least of human
immortality.



Boyle also noted, as did his contemporary Henry More, the Cambridge
Platonist, the occurrence of ecstasies. Boyle, like More, took the
existence of ecstasies seriously and, accepting the literal meaning of
the term, thought that such experiences showed the actuality of
non-corporeal, out-of-body, experiences. Boyle indeed offers the case
as a refutation of the Aristotelian view that images are required for
human thinking. Locke was more cautious on the issue: "whether
that, which we call *Extasy*, be not dreaming with the Eyes
open, I leave to be
 examined."[53]



Thus, for Boyle, souls were almost certainly Cartesian souls, though
as mentioned earlier he hesitates about whether or not the human soul
may not be a substantial form (BW, 5:300, Birch 1772, III:12).



Given that souls are incorporeal adjuncts of the body, it follows that
they are not *materially* destructible, and that the laws of
interaction between soul and body are not laws of natural philosophy.
Why grass *looks* green is a feature of the world which God
decided upon and upholds. His reasons for this decision, says Boyle,
were no doubt weighty, but they are, as to us, arbitrary (see, e.g.,
BP 2:62, BOA SS3.5.1, p 247; 2:105, BOA 3.5.21, p 258; 9:40;
36.46v). Now, if our souls are non-material, that demolishes at least
one philosophical barrier to a belief in an after-life such as is
promised by Christianity. (For a detailed discussion of Boyle's
views on perception see Anstey 2000.)