Locke, Plantinga, and the Aquinas/Calvin Model(1)

J. J. MacIntosh

Since our allotted time is short, we must take as read prefatory remarks concerning the fact that Warranted Christian Belief is provocative and interesting, and contains many deserving-of-discussion bits which will go undiscussed in this note. In fact, to do justice to Plantinga's book, which contains various important reevaluations of earlier positions, something like a line by line commentary would be required, for there are numerous places where dug in heels are appropriate, where one wants to say, "No, wait, that's not quite right," and where acquiescing by silence allows the discussion to move just that little bit more off line. Plantinga complains of Hume that he "writes with a certain surface clarity that disappointingly disappears on closer inspection [9]," but Hume is not the only philosopher of whom that might be said.(2) In what follows I confine myself to two of the many areas where I would be interested in Plantinga's comments.

1. Locke and tradition

The first, historical area of worry, concerns Plantinga's reading of Locke, and his placing of Locke in the context of intellectual history. I shall suggest that both are importantly skewed. Indeed, I think that so far from Locke being The Enemy, the very tradition in which Locke is situated is one with which Plantinga should find himself in complete sympathy. The leading writer in this tradition is Locke's much admired friend and slightly older contemporary, Robert Boyle, and indeed, as I read Plantinga I found myself thinking time and again of Boyle,(3) for reasons that I hope will become clear subsequently.

The second, less historical worry, concerns a central feature of the book, the Aquinas/Calvin model, with which I had considerable difficulty.

First then, Locke. Plantinga argues for two major theses. One is that Locke is anti-testimony. Plantinga writes:

there is testimony or credulity, whereby we learn from others, by believing what they tell us. ... The Enlightenment looked askance at testimony and tradition; Locke saw them as a preeminent source of error. The Enlightenment idea is that perhaps we start by learning from others--our parents, for example. Properly mature and independent adults, however, will have passed beyond all that and believe what they do on the basis of the evidence. But this is a mistake; you can't know so much as your name or what city you live in without relying on testimony. (Will you produce your birth certificate for the first, or consult a handy map for the second? In each case you are of course relying on testimony.) [147]

The other is that Locke is the "fountainhead" of this way of thinking. [82] Now there is a standard difficulty in reading Locke, namely that his love of truth was always stronger than his love of consistency, so that whenever his argument seemed to be taking him away from the truth he would simply contradict himself.(4) As Peter Geach said, "Locke's Essay is like a mail-order catalogue, and you buy what suits you,"(5) but I think, nonetheless, that we shouldn't buy what Plantinga has.

With the rediscovery of Pyrrhic scepticism at the end of the sixteenth century, a number of religious issues arose. In particular, the question of the reliability of the gospels came under scrutiny, as did the possibility, in natural philosophy, of accepting, in Descartes' case, the evidence of the senses, but more plausibly in general, the evidence of other experimenters.(6) Throughout the century the courts as well were being faced with the difficulty of deciding what should count as acceptable evidence, a problem which accelerated the acceptance of the new notion of facts.(7)

Descartes's decision was to accept the sceptical position and try to combat it head-on. Others, from Grotius through Chillingworth and Tillotson to Robert Boyle and Isaac Newton, sidestepped the issue, arguing that the kind of demonstration demanded by the sceptic was unrealistic.(8) Alternatively, it was acceptable, but then something which was for practical purposes just as good as demonstrated knowledge was readily available to us.

The kind of demonstration that was being set aside as being unrealistically rigorous was a peripatetic notion. It stemmed from the Aristotelian desire to have strict demonstrations of scientific results. We should start from principles, which were taken to be necessarily true (though provided by experience), and proceed by valid arguments to a conclusion which would (therefore) also be necessarily true.(9) Thus Aristotle:

It is clear too that if the propositions from which a deduction proceeds are universal, then it is necessary for the conclusion of such a demonstration, i.e. of a demonstration simpliciter, to be eternal. There is therefore no demonstration of perishable things, nor any understanding of them simpliciter but only incidentally, because nothing holds of them universally but only at some time and in some way.(10)

This view was constant throughout the high middle ages, and in the late fifteenth century Petrus Garsia, bishop of Ussellus in Sardinia, remarked "To assert that É experimental knowledge is science or a part of natural science is ridiculous, wherefore such magicians are called experimenters rather than scientists. Besides, magic, according to those of that opinion, is practical knowledge, whereas natural science in itself and in all its parts is purely speculative knowledge."(11) Seventeenth century scholastics (and logic texts) typically accepted without demur the requirement that the premises of scientific syllogisms be necessarily true. Thus Pierre du Moulin (the elder) writes, "Science is a certaine knowledge of a thing certaine, whose proof is drawne from the cause. To haue the Science of a thing, two certainties are required. The one is, that the thing be certaine of it selfe and vnchangeable. The second is, that the perswasion which wee haue of it be firme and cleare. If either of these two certainties be wanting it is not Science, but opinion. For a man may haue a doubtfull opinion of a thing certaine. As he that doubteth whether there be a God." Moreover these certainties are universal truths. "If a man know certainly a thing because he seeth it, or toucheth it, that is neither called Science, nor Faith, nor opinion, but sense, which knoweth only things singular: but Science is of things vniversall." And the way to arrive at these truths is by demonstration:

A Demonstratiue Syllogisme is that which giveth or bringeth certaine Knowledge of the conclusion. ... such questions or conclusions wherein the attribute is a mutable or casuall accident, cannot be proved by demonstration: because these accidents haue no certaine and assured cause ... . But those questions are demonstrable, whose attribute is a proper and immutable accident ... . For example these questions may be proved by demonstration.
A transparent bodie is without colour.

Eunuches are never bald.

Fixt starres doe twinckle.

The Moone suffers obscuritie.

Of all estates Oligarchie is the most subiect to civill warre.

Lines parallel never meet.

Under the scorching Zone it is very hot.(12)

In France Du Moulin's theme was echoed by Gassendi ("A syllogism whose premisses are necessary or clearly true is an apodeictic, demonstrative or scientific syllogism"(13)) and by Arnauld, who set out the points involved very clearly:

A true demonstration requires two things: first, that the content include only what is certain and indubitable; the other, that there is nothing defective in the form of the argument. Now we will certainly satisfy both of these if we observe the two rules we have laid down.

The content will include only what is true and certain if all the propositions asserted as evidence are:

Either definitions of words that have been explained, which, since they are arbitrary, cannot be disputed);

Or axioms that have already been granted and should not be assumed if they are not clear and evident in themselves ...;

Or previously demonstrated propositions that have consequently become clear and evident by virtue of the demonstration;

Or the construction of the thing itself in question, whenever there is some operation to be performed. This should be as indubitable as the rest, since the construction should have been previously shown to be possible, if there had been any doubt about it.(14)

In England that indefatigable popularizer John Newton noted that "Demonstration É amongst Logicians É is sometimes taken for every certain and clear proof," but "here it is strictly taken for a scientifical Syllogism."(15) And finally, at the very end of the century we find a popular translation of Burgersdijck claiming that "Every Question does not admit of a Demonstration Why; but only that which is true, and has a certain and immutable Cause of its Truth."(16)

By the time of Locke and Boyle the paradigm of this sort of demonstration was provided by mathematical demonstrations.(17) However, Aristotle's other point about the need to match the standard of proof with the subject matter at hand was also standardly invoked,(18) and it was generally accepted that something other than demonstration was appropriate in theology, in law, and in experimental philosophy. When discussing God's existence, Boyle tells us, we are "not to expect Metaphysical or rigid Demonstrations of a Deity"; nonetheless "a moral Demonstration may be sufficient."(19) But what is a moral demonstration?

[B]esides 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 ... . There are also physical demonstrations, where the conclusion is evidently deduced from physical principles: such as ex nihilo nihil fit: ..., 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, such as those, 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 received rules of prudence and principles of practical philosophy. And this third kind of probation, though it comes behind the two others in certainty, yet it is the surest guide, which the actions of men, though not their contemplations, have regularly allowed them to follow.(20) ... And this is considerable in moral demonstrations, that such may consist, and be, as it were, made up of particulars, that are each of them but probable; of which the laws established by God himself among his own people, as well as the practice our courts of justice here in England, afford us a manifest Instance in the case of murder and some other criminal cases.(21) For, though the Testimony of a single witness shall not suffice to prove the accused party guilty of murder; yet the testimony of two witnesses, though but of equal credit, that is, a second testimony added to the first, though of itself never a wit more credible then the former, shall ordinarily suffice to prove a man guilty; because it is thought reasonable to suppose, that, though each testimony single be but probable, yet a concurrence of such probabilities, (which ought in reason to be attributed to the truth of what they jointly tend to prove) may well amount to a moral certainty, i.e. such a certainty, as may warrant the judge to proceed to the sentence of death against the indicted party.
To apply these things now to the Christian religion: if you consider with how much approbation from discerning men, that Judicious observation of Aristotle has been entertained, where he says, that it is as unskilful and improper a thing, to require mathematical demonstrations in moral affairs, as to take up with moral arguments in matters mathematical; you will not deny but that those Articles of the Christian religion, that can be proved by a moral though not by a metaphysical or physical demonstration, may, without any blemish to a man's reason, be assented to; and that consequently (by virtue of foregoing considerations) those other articles of the Christian faith that are clearly and legitimately deducible from the so demonstrated truths, may likewise, without disparagement, be assented to.(22)

Now, how does testimony tie in with experience? Well, on occasion the two terms take in each other's washing. Thus Boyle again:

I call that personal experience, which a man acquires immediately by himself, and accrues to him by his own sensations, or the exercise of his faculties, without the intervention of any external testimony. It is by this experience, that we know, that the sun is bright; fire hot; snow cold and white; that upon the want of aliments we feel hunger; that we hope for future goods; that we love what we judge good, and hate what we think evil; and discern, that there is a great difference between a triangle and a circle, and can distinguish them by it.
By historical experience I mean that, which, though it were personal in some other man, is but by his relation or testimony, whether immediately or mediately, conveyed to us. It is by this, that we know, that there were such men as Julius C¾sar, and William the Conqueror, and that Joseph knew that Pharaohhad a dream, which the Egyptian wise men could not expound.

By theological experience I mean that, by which we know, what, supposing there is some divine revelation, God is pleased to relate or declare concerning himself, his attributes, his actions, his will, or his purposes, whether immediately, (or without the intervention of man) as he sometimes did to Job and Moses, and constantly to Christ our Saviour; or by the intervention of angels, prophets, apostles, or inspired persons, as he did to the Israelites, and the primitive Christian church; and does still to us, by those written testimonies we call the Scriptures.

By personal experience we know, that there are stars in heaven; by historical experience we know, that there was a new star seen by Tycho and other astronomers in Cassiop¾a, in the year 1572, and by theological experience we know, that the stars were made on the fourth day of the creation.

By this you may see, that I do not in this discourse take experience in the strictest sense of all, but in a greater latitude, for the knowledge we have of any matter of fact, which, without owing it to ratiocination, either we acquire by the immediate testimony of our own senses and other faculties, or accrues to us by the communicated testimony of others.(23)

Boyle follows this up by arguing for two consequent propositions with immediate theological implications: "We ought to believe divers things upon the information of experience, (whether immediate, or vicarious) which, without that information, we should judge unfit to be believed, or antecedently to it did actually judge contrary to reason," and "That we ought to have a great and particular regard to those things, that are recommended to our belief, by what we have reduced to real, though supernatural, experience."(24)

Thus Boyle. Incidentally, Boyle is in general committed to the notion of testimony in order to prove the correctness of Christianity, and to that end discusses at length the notion of an acceptable testimony.(25) He holds that God's existence is (almost) obvious ("God has vouchsafed men evidence enough of the truth of Christianity, to convince prudent men; th not to satisfy the Scepticks and silence Cavillers."(26)), and that what is necessary, given God's existence, is to decide on the correct instituted religion. It is the miracles of Christianity that show it, conclusively in Boyle's view, to be the correct religion. He was aware that one's birthplace could but often does influence one's religion: "others againe, who I fear make farr 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 up on the same grounds that would have made them Mahometans if they had been born & bred in Turky,"(27) but, Boyle felt, there were good reasons (a) to accept the accounts of Christian miracles on testimony, and (b) to notice that, given the miracles, Christianity was clearly the religion intended by God for humanity.(28)

So far Boyle. But perhaps Plantinga is right, and Locke has quite a different view of the place and worth of testimony? Perhaps, as he says, Locke saw tradition and testimony as "a preeminent source of error"? Well, no. Most of the Restoration intelligentsia saw enthusiasm as one of the great dangers of the interregnum period,(29) and not surprisingly found that sort of testimony suspect. But as far as testimony in general goes there is no suspicion of it in Locke any more than there is in Boyle. Knowledge, for Locke, is a term of art: it requires certainty. But certainty, being consequent upon demonstration, is not in general available to us: "He that will not eat, till he has Demonstration that it will nourish him; he that will not stir, till he infallibly knows the Business he goes about will succeed, will have little else to do, but to sit still and perish."(30) However, "where demonstrative Proofs, and certain Knowledge are not to be had" we may make use of what Locke calls Judgment.(31) Now, when we "judge the Proposition to be true" by something less than a demonstration, we have what Locke calls Probability.(32) And how do we gain this "probability"? Well, typically by reliable testimonies, though not by relying simply on the opinions of others. If that were to be our "ground of Assent, Men have reason to be Heathens in Japan, Mahometans in Turkey, Papists in Spain, Protestants in England, and Lutherans in Sweden."(33) However,

when any particular matter of fact is vouched by the concurrent Testimony of unsuspected Witnesses, there our Assent is also unavoidable. Thus: That there is such a City in Italy as Rome: that about one thousand seven hundred years ago, there lived in it a Man, called Julius Caesar; that he was a General, and that he won a Battel against another called Pompey. This, though in the nature of the thing, there be nothing for, nor against it, yet, being related by Historians of credit, and contradicted by no one Writer, a Man cannot avoid believing it, and can as little doubt of it, as he does of the Being and Actions of his own Acquaintance, whereof he himself is a Witness.(34)

Locke goes on to notice that, particularly in the case of historical records, we could wish "we had more of them, and more uncorrupted," but that when we have copies of copies, we can never gain, but at best keep, and will often lose, probability. However, perhaps enough has been said to show that, to the extent that Boyle and Locke can serve as typical figures of what Plantinga calls the "Enlightenment,"(35) it is simply not true that "The Enlightenment looked askance at testimony and tradition." [147](36)

2. The Aquinas/Calvin Model

Plantinga introduces the Aquinas/Calvin model as follows:

I propose ... to give a model of theistic belief's having warrant ... . The rough idea is this: to give a model of a proposition or state of affairs S is to show how it could be that S is true or actual. The model itself will be another proposition (or state of affairs), one that is such that it is clear (1) that it is possible and (2) that if it is true, then so is the target proposition. From these two, of course, it follows that the target proposition is possible. In this chapter, I shall give a model of theistic belief's having warrant: the Aquinas/Calvin (A/C) model. [168]

So we have two propositions (or states of affairs), one of which is a model, in this sense of the term (which is "more concrete" than "the logician's sense of model" but "more abstract" than the use of model in which one speaks of model aeroplanes, artists' models, or role models. [168]) Let's call the proposition which is the model, M, and the goal or target proposition which is to be shown possible, G. Now, what exactly is the claim here?

I can think of three possibilities to try and fit this paragraph's outline of what a model is. The trouble is, none of them fit it properly, and none of them seem to have very much to do with what the rest of the book tells us that the Aquinas/Calvin model is. Still, since Plantinga is here, I'd like to exhibit my confusion so that he can explain this notion more fully.

First, then, the three possibly unacceptable readings.

(1) The most obvious possibility is that, for any model and any goal proposition (or state of affairs) we have something like

<> M,
M --> G
Therefore <> G

The problem is, this argument is invalid,(37) as is clear from the case where M is any contingent falsehood, and G is any necessary falsehood. But Plantinga has emphasized true: "if M is true then so is G." So perhaps the claim is that, with respect to such models,

(2) In any possible world in which M is true, G is true too. That is, [] (M --> G). Then we have a valid argument:

<> M,
[] (M --> G)
Therefore <> G

I'm inclined to believe that this is what Plantinga had in mind, since it does give us a valid argument, but the problem with this reading is that he does not emphasize the need to show that M --> G is necessarily true, and does not indeed seem to be arguing for that claim. However, it may be that its necessity in this particular case is meant to be obvious from the text.

(3) One final possible reading. Perhaps the claim is that in any possible world in which M is true, then, in that world, M --> G is true too. Once again, since "[(M --> G)  and M] --> G" is a theorem, and hence so too is <> [(M --> G) and M] --> <> G.  we would have a valid argument:

<> [(M --> G) and M]
Therefore, <> G

But this does not seem to fit the text, either, since that tells us that we first get M, observe its clear possibility, and then show that if M is true, so is G. (And then derive <> G.)(38)

Leaving that, however, for Plantinga to clear up if time and inclination allow, I should admit at once that, in terms of what Plantinga calls the "Aquinas/Calvin model," I found it very difficult to decide just what proposition or set of propositions was meant to fill the role of <> M, and what was filling the role of <> G, though perhaps that is simply the claim that some (or all?) theistic beliefs have warrant. Indeed, I had considerable difficulty in getting clear just what the model was, such that (a) its possible truth was transparent, and (b) some desired target proposition followed from it of necessity. It became clear almost at once, however, that the model proposition was going to be an extended conjunction. For in what follows, Plantinga tells us that a great many things are the case "according to the model." For example, we have a "natural knowledge of God [which] is not arrived at by inference or argument." [175] Moreover, "On the A/C model ... theistic belief as produced by the sensus divinitatis is basic." [177] Again, "On this model, our cognitive faculties have been designed and created by God." [179] Again, "according to the model, sin damages the sensus divinitatis and compromises its operation." [179n16] Again, "Suppose something like the A/C model is in fact correct: knowledge of God ordinarily comes not through inference from other things one believes, but from a sensus divinitatis." [180] Again, "according to the A/C model ... natural knowledge of God has been compromised, weakened, reduced, smothered, overlaid, or impeded by sin and its consequences [but] (on the model) the sensus divinitatis is restored to proper function by regeneration and the operation of the Holy Spirit. Again, according to the "extended model," "human beings as originally created ... had extensive and intimate knowledge of God."(39) [204]

Now, remember the notion of model with which we are working here. There is meant to be a proposition (possibly, I suppose, a large conjunction) "such that it is clear (1) that it is possible and (2) that if it is true, then so is the target proposition."

Let us take one of these conjuncts, say the claim that we have a "natural knowledge of God." If this is the possible proposition, what is the target proposition? What is our G?--that (some) knowledge claims about God are warranted? That would follow, for if we have knowledge of God, then that knowledge is warranted (otherwise it wouldn't be knowledge). And this would give us a necessitated conditional all right. But is it true that "we have a natural knowledge of God" is clearly possibly true? Is our having a sensus divinitatis something that is clearly possible?(40)

I am, I confess, confused about Plantinga's intentions here. I would like to hear more, and more clearly, about the proposition or propositions that are supposed to be clearly possible, and about the proposition or propositions that are entailed by them. I will simply note that I think one of the strengths of the ontological argument is that it yields the result that God's existence is either necessary or impossible, a point with which Plantinga agrees. From this it follows at once that, with regard to God's existence at least, and perhaps with regard to any proposition attributing a property to God,(41) modality collapses, for we will then have

[] God exists v [] God does not exist

i.e., <> God exists --> [] God exists(42)

Similarly, for any F, such that necessarily either God has it, or lacks it, we will have:

[] Fg v [] ¬ Fg

i.e., <> Fg --> [] Fg

To what extent this affects Plantinga's task of showing that his model proposition is clearly possible, I do not know (though I have some possibly warranted beliefs).


1. In what follows references in square brackets in the text are to Alvin Plantinga, Warranted Christian Belief (New York: Oxford University Press, 2000). References to Locke are to John Locke, An Essay Concerning Human Understanding, ed. P. H. Nidditch (Oxford: Clarendon Press, 1975), hereafter Essay. References to Boyle are to Robert Boyle, The Works of the Honourable Robert Boyle, ed. Thomas Birch, 6 vols. (London, 1772, reprinted Hildesheim: Georg Olms, 1966), hereafter Works, and to Robert Boyle, Letters and Papers of Robert Boyle, ed. Michael Hunter (Bethsada MD: University Publications of America, 1990), hereafter BP. In my transcriptions of the Boyle Papers I have here omitted Boyle's deletions. Like many workers on the Boyle manuscripts I owe a considerable debt of gratitude to the Librarian and staff of the Royal Society Library for their help and interest. Work on this paper was supported in part by a research grant from the Social Sciences and Humanities Council of Canada, and by a fellowship from the Humanities Institute of the University of Calgary.

2. It is, in fact, true of most good philosophers: they write with surface clarity, but a little digging (often their own, later, digging) discloses gaps, ambiguities, obscurities, and sometimes positive inconsistencies. As Robert Boyle said, "Philosophers are subject to humane frailties in general, & not only so, but to personal weaknesses & defects, as lazynes, envy, ambition, Arrogance, Hatred &c. They often contradict one another, and not seldom themselves. ... many of them have been actually mistaken, & some of them grossly so." [BP 9:34]

3. Plantinga is, I think, sometimes misled by the difference in language between the seventeenth and the twenty-first century. Often what Boyle and Locke have to say in terms of reason will transpose without loss into Plantinga's warrant..

4. A. J. Ayer once remarked, speaking of the coherence theory of truth, "Part of the heroism of philosophers is that when they do make a mistake they cling to it even when, as in this case, the consequences are truly outrageous." Berkeley often displayed this sort of heroism; in Locke we find heroism of a different, Whitmanesque, sort: if the consequences are going to be outrageous, stop short and insert a judicious negation sign.

5. P. T. Geach, 'Identity', Review of Metaphysics, 21, 1967-8, 3-12, 12.

6. The unreliability of reports of other, especially earlier, experimenters is a constant problem for the experimental philosophers of the Restoration. Here, for example, is Boyle on an experiment reported by Berigardus (1578-1677):

though something like what is here proposed to be done, may be performed, and other phaenomena of the experiment such as he seems not to have been acquainted with, may be also exhibited, after the manner I have elsewhere particularly set down; yet he must have good luck that performs it only by the directions here given by our author, who by omitting one of the chief ingredients, and some requisite circumstances, appears indeed manifestly enough to have heard of such an experiment, but without seeming to have sufficiently known, what he pretends to teach, (at least as far as his bringing this experiment as a proof, and the obscure style, he is wont to employ in the little I have yet read of his book, permits me to judge.) [Boyle, Works 2:653. For details of the experiment see Works 2:696-8.]

7. In the earlier seventeenth century the commonest use of the term was a legal one: fact = "an evil deed, a crime." (Oxford English Dictionary, Fact, 1c.) This usage is still found in legal phrases such as "an accessory after (or before) the fact." Locke often talks simply of "matters of fact" in what appears to be our sense of the term, though his consciousness of its comparative novelty may be seen in the Essay at 4.16.5 ("some particular Existence, or, as it is usually termed, matter of fact"). However, the normative use is still present in the Essay at 2.27.22: "But is not a Man Drunk and Sober the same Person, why else is he punish'd for the Fact he commits when Drunk, though he be never afterwards conscious of it?" The notion of fact, as Zeno Vendler has pointed out, is not as straightforward as philosophers often assume. See Zeno Vendler, "Telling the Facts," (in F. Kiefer and J. Searle, eds., Speech Act Theory and Pragmatics [Dordrecht: D. Reidel, 1979], reprinted in P. A. French, T. E. Uehling, Jr, H. K. Wettstein, eds., Contemporary Perspectives in the Philosophy of Language [Minneapolis: University of Minnesota Press, 1979], 220-232); and "Facts and Events," and "Effects, Results, and Consequences," chapters 5 and 6 of Vendler's Linguistics in Philosophy (Ithaca: Cornell University Press, 1967).

8. The details of this development are set out in Henry G. Van Leeuwen, The Problem of Certainty in English Thought 1630-1690 (The Hague: Martinus Nijhoff, 1970). See also Barbara Shapiro, "The Concept 'Fact': Legal Origins and Cultural Diffusion," Albion, 26.2, 1994, 227-52, Lorraine Daston, "The Factual Sensibility," Isis, 79, 1988, 452-67, Lorraine Daston, "Marvelous Facts and Miraculous Evidence in Early Modern Europe," Critical Inquiry 18, and for the continuation of the story in the eighteenth century, M. J. Ferreira, Scepticism and Reasonable Doubt (Oxford: Clarendon Press, 1986).

9. Prior Analytics, 1.1, 24a27-30: "a deductive proposition ... will be demonstrative, if it is true and assumed on the basis of the first principles of its science," and Prior Analytics 1.30, 46a17-21: "it is the business of experience to give the principles which belong to each subject. I mean for example that astronomical experience supplies the principles of astronomical science ... . Similarly with any other art or science." [The Complete Works of Aristotle, ed. Jonathan Barnes (Princeton: Princeton University Press, 1984)] Barnes has emphasized that "Aristotle was not telling the scientist how to conduct his research: he was giving the pedagogue advice on the most efficient and economic method of bettering his charges." (Aristotle, Posterior Analytics, translated with a commentary by Jonathan Barnes [Oxford: Clarendon Press, 2nd ed., 1994], xviii).

10.  Aristotle, Posterior Analytics, translated with a commentary by Jonathan Barnes (Oxford: Clarendon Press, 2nd ed., 1994), 1.8, 75b 21-6. The Posterior Analytics was the clear source of the discussions on demonstration in the logic texts of the time with, in many cases, even the examples persisting unchanged. As Barnes remarks in his Introduction (xi), "If a Bacon or a Locke sternly rejected the ancient pleasures of Aristotelianism, it was only the perverted excesses of scholasticism which fell to their condemnation: the original beauties of the Analytics still flashed and excited."

11.  Quoted in J. R. Partington, A History of Chemistry 2 vols. (London: Macmillan, 1961), 2:10.

12.  Peter Du Moulin, The Elements of Logick, trans. Nathanael DeLawne (London, 1624), 162-5. For discussion of these examples in Aristotle see, e.g., De Anima 418b 4-6, transparency; History of Animals 632a 4-5 and Generation of Animals 784a 6, baldness and eunuchs; De Caelo 290a 19-20 and Posterior Analytics 78a 30-78b 3, the twinkling of stars; and Posterior Analytics 75b 33-5, eclipses of the moon.

13.  Gassendi, Pierre, Institutio Logica, trans. Howard Jones (Assen: van Gorcum, 1981 [1658]), Canon XVI, 144.

14.  Arnauld, Antoine, and Pierre Nicole, Logic or the Art of Thinking, trans. and ed. Jill Vance Buroker (Cambridge: Cambridge University Press, 1996), part IV, ch 8, 323-4 (pagination as in the 5th, 1683 edition).

15.  John Newton, An Introduction to the Art of Logick (London, 1671), 105. Newton gives an expanded version of one of Du Moulin's examples:

That which by the interposition of the earth cannot be enlightened by the Sun-beams, doth suffer an Eclipse of the Sun-light,

But the Moon, the earth being interposed cannot be enlightened by the Sun-beams,

Therefore the Moon &c. (118)

16.  Franco Petri Burgersdijck, Institutionum logicarum (various editions, translated and annotated as Monito Logica or An Abstract and Translation ofBurgersdicius His Logick by a Gentleman [London, 1697]), 102.

17.  This slightly oversimplifies the matter. For the full story see Locke, Essay, 4.17.3.

18.  "Our discussion will be adequate if it has as much clearness as the subject-matter admits of: for precision is not to be sought for alike in all discussions, any more than in all the products of the crafts." (Nicomachean Ethics, 1094b12-14)

19.  BP 2:77, 2:84.

20.  This certainty, Locke remarked, 'is not only as great as our frame can attain to, but as our Condition needs.' (Locke, Essay, 4.11.8.)

21. Correcting Boyle 1772 'causes' to ms. reading 'cases' (BP 2:113).

22. In manuscript Boyle wrote but eventually decided to omit the following;

Wee may indeed wish that about matters that doe soe nearly concerne us we had soe much evidence to make our determinations by as might enable us to answer fully all objections & scruples. But tho we may wish this: yet we must [not] always expect it, nor think resolutions Unreasonable or Precipitate that are made upon inducements that are not soe clear & satisfactory as such an Evidence would be. (BP 2:114)

23. The Christian Virtuoso, The First Part, 1690, Works, 5:525.

24. The Christian Virtuoso, The First Part, 1690, Works, 5:526, 529.

25. See, e.g., BP 3:117.

26. BP 5:32v.

27. BP 4:60.

28. For a discussion of the views of Locke and Boyle on this issue see J. J. MacIntosh, "Locke and Boyle on Miracles and God's Existence," in M. Hunter, ed., Robert Boyle Reconsidered (Cambridge: Cambridge University Press, 1994), 193-214.

29. The English word 'enthusiasm' derives from the Greek entheos, being possessed by a god, and the term was standardly used in the seventeenth century to denote not merely the fourth century heretics who were given that label but those contemporaries who believed themselves to be the direct conduit of a revelation from God. Thomas Edwards, in The First and Second Part of Gangr¾na: or A Catalogue and Discovery of many of the Errours, Heresies, Blasphemies and pernicious Practices of the Sectaries of this time, vented and acted in England these four last years, The third Edition, corrected and much Enlarged (London, 1656), includes the Enthusiasts among the "sixteen heads or sorts of Sectaries" chiefly responsible for "the Errours, Heresies, Blasphemies" which he is attacking; Thomas Sprat in his History of the Royal Society (1667) vigorously attacked the earlier enthusiasts, and Locke found it worthwhile to insert a chapter 'Of Enthusiasm" in the fourth and subsequent editions of the Essay. See further Michael Hunter, "The Debate Over Science," in J. R. Jones, ed., The Restored Monarchy 1660-1668 (London: The Macmillan Press, 1979).

30. Locke, Essay, 4.14.1.

31. Locke, Essay, 4.14.3.

32. Locke, Essay, 4.15.1.

33. Locke, Essay, 4.15.6.

34. Locke, Essay, 4.16.8

35. I put Enlightenment in scare quotes because I think of it as a term designating eighteenth century thinkers and their outlooks, but I may simply be wrong about common usage here.

36. Incidentally, Locke also realized that the testimony of our senses, our memory, and our knowledge of the way the world works, are not a single simple package, but something which provides us with interlocking testimony for their several accuracies, as well as a means of checking their frequent inaccuracy: See, e.g., Locke, Essay, 4.11.7: "Our Senses, in many cases bear Witness to the Truth of each other's Report, concerning the Existence of sensible things without us. He that sees a Fire, may, if he doubt whether it be anything more than a bare Fancy, feel it too; and be convinced, by putting his Hand in it. Which certainly could never be put into such exquisite pain, by a bare Idea or Phantom, unless that the pain be a fancy too: Which yet he cannot, when the Burn is well, by raising the Idea of it, bring upon himself again." The notion that this large, varied, interlocking, and indispensable set of knowledge providers is on all fours with the single and dispensable CMP is something that requires considerably more by way of defence than it receives in Warranted Christian Belief. Or, in my view, than it receives in Alston's Perceiving God.

37. We cannot get from M --> G to <>M --> <>G, though we can get this result in normal systems from [](M --> G):

1) (M --> G) --> (¬G--> ¬M)                          T

2) [](M --> G)--> (¬G --> ¬M)]                       1, N

3) [](M --> G) --> [](¬G--> ¬M)                      2, K

4) [] (¬G--> ¬M)--> ([] ¬G --> []¬M)                K

5) ([] ¬G --> []¬M) --> (¬[]¬M --> ¬[] ¬G)        T

6) (¬[] ¬M --> ¬[] ¬G) --> (<>M --> <>G)         Df <>

7) [] (M--> G) --> (<>M --> <>G)                     3,4,5,6, Syll x 3

38. In his response Plantinga noted that the second possibility catches his intention.

39. This claim is apparently meant to be non-metaphorical, so it is in order to ask "when did they have this knowledge?" Did Lucy have it, for example? Plantinga says [207] that the model "need not take a stand" on the question of whether or not the Adam and Eve story is true, but there should be some intelligible, and preferably plausible, answer to the question, and it is not clear to me what it could be.

40. In discussion Plantinga said that M, the model proposition, was meant to be the conjunction of theism (itself a conjunction of a variety of claims) and the claim that human beings have a sensus divinitatis, which, when it functions properly, produces theistic belief. And G is the claim that some theistic belief is warranted.

41. Assuming that the properties God has, God has necessarily. Whether or not this assumption is plausible for some or all of God's qualities depends in part on the notion of necessity being invoked. For further discussion see J. J. MacIntosh, "Aquinas on Necessity," American Catholic Philosophical Quarterly, 72, 1998, 470-503.

42. On this topic see further, Robert M. Adams, "The Logical Structure of Anselm's Arguments," Philosophical Review, 80, 1971, 28-54; J. J. MacIntosh, "Theological Question Begging," Dialogue, 30, 1991, 531-547; and Brian F. Chellas, and Krister Segerberg, "Modal Logics With the MacIntosh Rule," Journal of Philosophical Logic 23, 1994, 67-86.