What's Wrong With Plantinga's Proper Functionalism?

(Reposted with minor revisions)

I. Plantinga's Reformed Epistemology and His Mature Account of Warranted Belief
Since the 60s, Alvin Plantinga has been arguing that belief in God is "properly basic". That is, like belief in material objects, the past, and other minds, belief in God can be rational in a direct, non-inferential way, wholly apart from propositional evidence and argument. This thesis constitutes the core idea of his version of so-called "Reformed Epistemology".

Plantinga's mature defense of his thesis is grounded in a proper functionalist version of epistemic externalism. Plantinga summarizes his account as follows:

"Put in a nutshell, then, a belief has warrant for a person S only if that belief is produced by cognitive faculties [e.g., perception, memory, introspection, reason, and testimony -EA] functioning  properly (subject to no dysfunction) in a cognitive environment that is appropriate for S's kind of cognitive faculties, according to a design plan that is successfully aimed at truth."[1]

So that's what's required for a belief to have any warrant at all on Plantinga's account. But he allows that warrant admits of degrees, and he ties the degree of warrant a belief enjoys to the degree of firmness with which it is believed: "We must add, furthermore, that when a belief meets these conditions and does enjoy warrant, the degree of warrant it enjoys depends on the strength of the belief, the firmness with which S holds it."[2] Thus, for such a belief to have a degree of warrant sufficient for knowledge, it must be held with a very high degree of firmness.

Putting these points together, Plantinga's account can be summed up as follows:
I.   Conditions of warrant are not met = no warrant (whether the belief is held firmly or not)
II.  Conditions of warrant are met + low degree of firmness = low degree of warrant.
III. Conditions of warrant are met + high degree of firmness = high degree of warrant.

So that's Plantinga's account of warranted belief in a nutshell. But how does this account connect to his account of warranted theistic belief in particular?

II. Plantinga's Mature Account of Warranted Theistic Belief: The A/C Model[3]
Plantinga argues that it's epistemically possible (consistent with what we know or reasonably believe) that God has designed us in such a way that we are naturally endowed with a cognitive faculty -- what he (following John Calvin) calls the sensus divinitatis -- that, when functioning properly in an epistemically congenial environment, spontaneously and reliably produces true beliefs about God. So, for example, when one looks at the starry heavens, the sensus divinitatis is (when functioning properly) naturally disposed to spontaneously trigger the belief, "God made all this"; when doing something wrong, it's disposed to trigger the belief, "God disapproves of what I've done"; etc. Therefore, if such belief meets all of the conditions of warrant  -- viz., (a) it's produced by a properly functioning cognitive faculty (viz., the sensus divinitatis), (b) the faculty is successfully aimed at truth, and (c) the environment in which such beliefs are formed is epistemically congenial --, Plantinga's account entails that such belief enjoys at least some measure of warrant. And if (d) such belief is held with a very high degree of firmness, the degree of warrant it enjoys is sufficient to constitute knowledge (assuming the belief isn't subject to undefeated defeaters).[4]

We've now looked at Plantinga's account of warranted belief in general and his account of warranted theistic belief in particular. It is now time to take a look at his account of warranted Christian belief.

III. Plantinga's Mature Account of Warranted Christian Belief: The Extended A/C Model[5]
Very roughly, on Plantinga’s model of warranted Christian belief, the Holy Spirit acts on the believer by repairing the sensus divinitatis  from the ravages of sin, so that it naturally, spontaneously, and reliably produces true belief about God in the basic (i.e., non-inferential) way. It also repairs the person's affective equipment, so that it is no longer hostile to God and his purposes, but is rather attracted to them and delights in them. Finally, the Holy Spirit functions as an analogue to a properly functioning cognitive faculty by acting directly on the "heart" of a person to produce belief in the core truths of Christianity (what Plantinga calls the Great Things of the Gospel) when they are presented to them (if the person wills to accept the gospel message).  Therefore, as with warranted theistic belief as described in Plantinga's A/C model,  if Christian belief formed in the way described in his Extended A/C model meets all the conditions of warrant, i.e., (a) it's produced by properly functioning cognitive faculties[6], (b) the faculties are successfullly aimed at truth, and (c) the environment in which they're formed is epistemically congenial, then it enjoys at least some measure of warrant. And if (d) (due to the internal instigation of the Holy Spirit) the belief is held with a very high degree of firmness, the degree of warrant it enjoys is sufficient to constitute knowledge (again, assuming the belief isn't subject to undefeated defeaters).

We've now seen a sketch of Plantinga's account of warranted belief in general, warranted theistic belief, and warranted Christian belief. What to make of these accounts? I mention eight criticisms below from the literature that have real bite (for more elaboration, click on the links).

 IV. Criticisms of Plantinga's Account of Warranted Belief that Have Real Bite
With respect to his accounts of warranted theistic and Christian belief: (i) His analysis of warranted Christian belief can't adequately account for the variability of belief among Christians[7]; (ii) his postulation of a sensus divinitatis in human beings is at odds with the empirical evidence regarding the demographics of theistic belief[8]; and (ironically) (iii) his account entails that the belief of most Christians has little by way of warrant[9]. And of course there's (iv) the Great Pumpkin Objection. But deeper problems lie with his basic account of warrant (see below).

With respect to his account of warranted belief in general: (i) His case for a theistic version of proper functionalism is undercut[10]; indeed, (ii) his theistic version of proper function entails that no beliefs have warrant[11]; (iii) his proper functionalist amendment to straight reliabilism is unmotivated[12]; and (iv) his account of warrant is subject to counterexamples[13] with respect to both to the necessity and sufficiency of the conditions he proposes.

For these reasons, Plantinga's proper functionalism fails to show that Christian or theistic belief can be warranted in the basic or non-inferential way, or even how beliefs can be warranted in general.

[1] Warranted Christian Belief, p. 156.
[2] Ibid.
[3] (Plantinga calls his account of warranted theistic belief The A/C Model, inspired as it is by the writings of Aquinas and Calvin.)  The following is a rough summary of some key points in ch. 6 of Warranted Christian Belief.
[4] Question: If all human beings are endowed with a sensus divinitatis, then why do very many people fail to form theistic belief -- at least in the basic, non-inferential way Plantinga describes? Answer: The sensus divinitatis has been damaged by the Fall of Man and human sin. More on this in the next section.
[5] The following is a very rough summary of some key points in chs. 7-9 of Warranted Christian Belief.
[6] This part is a bit tricky. For, again, according to the model, the Holy Spirit doesn't produce warranted Christian belief via the cognitive faculty of the sensus divinitatis. Rather, it produces it by acting directly on the "heart" of the person. Therefore, strictly speaking, specifically Christian belief isn't produced by a reliable cognitive faculty, but rather by a reliable process. As you might have guessed, people have raised concerns about this. See, for example, Craig and Moreland's Philosophical Foundations for a Christian Worldview (IVP, 2003), pp. 168-169; Beilby, James. Epistemology as Theology: An Evaluation of Alvin Plantinga's Religious Epistemology (Ashgate, 2005), pp.151-153.
[7] Cf. Beilby, Epistemology as Theology, pp. 153-156.
[8] Cf. Maitzen, Stephen. "Divine Hiddenness and the Demographics of Theism" (Religious Studies 42 (2006), pp. 177-191.
[9] See, for example, Beilby. "Plantinga's Model of Warranted Christian Belief", in Peter-Baker, Deane. Alvin Plantinga (Cambridge University Press, 2007), p. 146; DeRose, Keith."Are Christian Beliefs Properly Basic?" APA Eastern talk, 1998. Available here; Chignell, Andrew. "Epistemology for Saints: Alvin Plantinga's Magnum Opus", Books & Culture (March/April 2002), p. 21.
[10] Cf. Wunder, Tyler. "Anti-Naturalism and Proper Function”, Religious Studies 44 (2008), pp. 209-224 (notes); Bardon, Adrian. “Reliabilism, Proper Function, and Serendipitous Malfunction”, Philosophical Investigations 30:1 (Jan. 2007), pp. 47-64 (notes); Graham, Peter. "Intelligent Design and Selective History: Two Sources of Purpose and Plan" (in Jonathan Kvanvig, ed. Oxford Studies in Philosophy of Religion, Volume 3, 2011). (A link to the paper can be found here)
[11] In addition to my formulation of the objection at the link above, see R. Douglass Geivett and Greg Jesson. "Plantinga's Externalism and the Terminus of Warrant-Based Epistemology", Philosophia Christi 3:2, pp. 329-340.
[12] Feldman, Richard. “Proper Functionalism”, Nous 27 (1993), pp. 34-50.
[13] See, for example, Greco, J. 2003. “Virtue and Luck, Epistemic and Otherwise,” Metaphilosophy 34:3, 353-6; Lehrer, Keith. "Proper Function vs. Systematic Coherence", in Kvanvig, Jonathan. Warrant in Contemporary Epistemology: Essays in Honor of Plantinga's Theory of Knowledge (Rowman & Littlefield, 1996), pp. 25-46, esp. pp. 32-33; Feldman, “Proper Functionalism”,  pp. 34-50; Senor, Thomas. “A Critical Review of Alvin Plantinga’s Warranted Christian Belief”, International Philosophical Quarterly 42:3, Issue 167 (September 2002), 395-396.


Angra Mainyu said...

Very nice post(s), EA.

Regarding the example of cosmic rays and the prime numbers, and Mike Almeida's reply to your point (and to Feldman's alternative), it seems to me that Plantinga's account does not require that the designer be unique, with a single plan, for the following reasons:

1. That's not stated by Plantinga, as one of the conditions (as far as I know).
2. In "Warrant and Designing Agents" Philosophical Studies 64: 203-215 (granted, it's from 1991, but I do not know of a change in his position), Plantinga considers Taylor's proposed counterexample of Clarence, a man who acquires the capacity for precognition and clairvoyance by chance.

Plantinga's first move (with regard to Clarence's case) is to suggest that it may not be possible to acquire a cognitive power by accident, because God is updating the world, etc. However, that kind of doubt might be raised just as much in the case of the cosmic rays example (i.e., would they be the result of God's design anyway?), and to many other examples; moreover, it doesn't seem to address the point against a conceptual connection between our origins and the possibility to have warranted beliefs.

Then, Plantinga assumes it's possible that Clarence would get precognition and clairvoyance by chance, and comes up with the example of a radio that gets better (it can receive more stations) after being thrown from a building. Plantinga claims that the design is adopted if not original, and proposes, as a solution to the clairvoyance case, that Clarence's cognitive system works differently now, and that this new way of working would be adopted by us (and by Clearance, and possibly by God), as a new design plan, and that, for that reason, his faculties are working according to the new design plan, and thus they can constitute knowledge.

The above suggest that the objection that the scientists are messing with God's original design (as an objection to your scenario about Jupiter's Moons) would not work, since modifications that are designed can also result in knowledge, apparently, on Plantinga's account (he does not seem to demand that God embraces the new design), regardless of whether the original designer had such modifications in mind.

exapologist said...

Hi, Angra. Thanks for your thoughtful remarks. Taylor's critique is penetrating, and the exchange nicely surfaces some weaknesses in Plantinga's account that seldom come up elsewhere.

Angra Mainyu said...


Thank you too for posting your critique of Plantinga's account as well, which I find pretty persuasive. By the way, your argument based on God's not being designed , despite the 'just for laughs' title, looks like a pretty good objection to me; the result is indeed funny, though (I see a potential objection, but it seems it's not available to someone's defending Plantinga's account, since it would debunk it from a different direction).

Regarding Plantinga's critique of Taylor, it's an interesting reply, though I'll say he makes a subtle mistake at the beginning.

More precisely, after Plantinga states the two essential premises of the dilemma, he says that there are two initial problems, and calls the second one the more interesting of the two. However, given the dilemma as stated, the appearance of the second problem is only artificially created by Plantinga's language.

Essentially, what Plantinga shows (using 'all men are mortal' and 'whales evolved from small land creatures' to illustrated his point) is that even if P1&¬P2 is doubtful and P1&¬P2 is doubtful, then it doesn't follow that P1 is doubtful.

Plantinga is right about that, but that's not a problem for Taylor's dilemma, as stated by Plantinga, since the dilemma is essentially of the form:

(1) If P, then ¬Q.
(2) If ¬P, then Pr(Q) ≤ Pr(R).
C: Pr(Q) ≤ Pr(R).

Here, P is the proposition that the concept of proper function is analyzable in terms of an actually designing agent, Q is the proposition that Plantinga's account is true and R is the proposition that reliabilism is true.
The conclusion actually follows:

i. Pr(Q)=Pr(Q&P) + Pr(Q&¬P)
ii. Pr(Q&P) = 0 (since P implies ¬Q, so 'P is true' and 'Q' are disjoint events).
iii Pr(Q&¬P) = Pr(Q¸ │¬P) Pr(¬P) ≤ Pr(R¸ │¬P) Pr(¬P) = Pr(R&¬P) ≤ Pr(R) [the first inequality follows from (2)]
iv. Pr(Q)≤Pr(R). [from 1 and 3]

I suppose someone might object to the use probability language in this context. I don't see why that would be problematic, but in any case, one can leave that aside and argue as follows:

5. If Plantinga's account is subject to counterexample, then it's false. [clear]
6. If Plantinga's account is false, then it's not a superior alternative to reliabilism. [clear; at best, they're equal]
7. If the concept of proper function is analyzable in terms of an actually designing agent, then Plantinga's account is subject to counterexample (premise 1 of Taylor's dilemma, as construed by Plantinga).
8. If the concept of proper function is analyzable in terms of an actually designing agent, then Plantinga's account is not a superior alternative to reliabilism. [from 5, 6, and 7].
9. If the concept of proper function is not analyzable in terms of an actually designing agent, then either Plantinga's account reduces to a version of reliabilism, or in any case it's not superior to reliabilism. [second premise of the dilemma].
10. If Plantinga's account reduces to a version of reliabilism, then it's not superior to reliabilism. [clear]
11. If the concept of proper function is not analyzable in terms of an actually designing agent, then Plantinga's account is not superior to reliabilism. [from 9 and 10]
12. Plantinga's account is not superior to reliabilism. [from 8 and 11].

The argument is valid.
Of course, Plantinga can still challenge the premises of Taylor's dilemma, and he does challenge Taylor's examples.
However, Plantinga's attempt at showing that there is a fundamental problem with the kind of reasoning behind Taylor's dilemma (as construed by Plantinga's in his reply to Taylor), does not succeed.

Angra Mainyu said...

It seems there are other, serious difficulties with Plantinga's whole approach to defending his accounts, like the following one:

1. Plantinga says that in order to show that a conceptual analysis of some concept is mistaken, a counterexample to needs to be clearly possible (page 208 of the paper I quoted).

2. He also questions whether a scenario is possible on the basis of whether God would actually allow anything to happen by change, since God is behind everything, and in that fashion, he questions that a person might acquire some cognitive function randomly.

3. Proper function can result from an agent adopting a new function, even if that new function comes about unintentionally. For instance (page 209), Plantinga considers the case of a radio that acquires new functions after falling accidentally, and then he says that once he's adopted the new function as proper, functioning as before would no longer be proper. But for that matter, if just by chance in some remote planet in a universe with infinitely many galaxies a tornado were to assemble a B747, then the plane would function properly or improperly as long as someone adopts the function.

There are numerous problems with his approach, but for example, let's consider the following scenario:

Richard is a non-theist, Jesús (from Spain) is a Christian who disagrees with Plantinga on many issues, and Chip agrees with Plantinga's account of proper function and of warrant.

Richard: "Let's assume that God does not exist, and consider scenario S [Richard describes S]. On S, it's intuitively clear that some people are mentally ill, so there is proper and improper function, but there is no designer".
Chip: "Granted, that's intuitively clear in the scenario. However, you're assuming that God does not exist, but that's far from being clearly possible. So, your objection to Plantinga's conceptual analysis fails."
Jesús: "Of course, God exists. But let's consider scenario T [Jesús describes T]. On T, it's intuitive that even though God exists, some animals weren't the result of design (not even the result of evolution), yet they're ill as well. So, proper and improper function do not conceptually require design."
Chip: "Granted, that's intuitively clear in the scenario. However, you're assuming that God would allow animals to come about by chance, but that's not clearly possible. Moreover, even if God possibly allows that, it's not clear that God would not immediately adopt the functions as a new design.
So, your objection to Plantinga's conceptual analysis fails."

It seems that if one accepts Plantinga's approach to defending his account, then no matter how intuitive a scenario in which there would be proper function but no design might be (or a scenario in which there would be knowledge but no design, for that matter), Chip can use Plantinga's approach to claim that Plantinga's conceptual analysis has not been defeated. That looks like an unfalsifiability engine, rather than a proper way of assessing a proposed analysis.

Side note: If someone suggests that illness does not required proper function (but it seems to me it does), one can modify the scenarios above and say that, say, they have a damaged heart, brain, etc., so that's not essential to my objections above.

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