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Showing posts from 2006

Conceivability, Possibility, and the Ontological Argument

I don’t want to go into a full-dress exposition of the ontological argument, because I think it would be distracting to a simple yet decisive objection to it. For our purposes, then, we can express its structure crudely as follows:

1. It’s possible that there is a necessary being.
2. If it’s possible that there is a necessary being, then a necessary being exists.
3. Therefore, a necessary being exists.

The argument is valid; so, if its premises are true, its conclusion follows of necessity. Well, what reasons can be offered for the premises?

Premise (2) is just an instantiation of Axiom S5 of S5 modal logic. The underlying idea of Axiom S5 is that what is necesssarily the case doesn't vary from possible world to possible world: if something is necessary in one possible world, it's necessary in every possible world. I accept Axiom S5; so I accept premise (2). That leaves us with premise (1). Is it more reasonable to believe it than not -- or at least: is it more reasonable to…

Outline of Section X of Hume's Enquiry Concerning Human Understanding

[In an effort to promote the habit of understanding a position before accepting or rejecting it, here is my attempt at providing a close outline of the relevant passage from Hume's writings in which he argues against the rationality of testimony-based belief in miracles: Section X of his An Enquiry Concerning Human Understanding]

Section X, Part I:
0. Introductory stuff:

0.1 Quick summary of theologian John Tilotson's argument against Transubstantiation.
0.1.1 Scripture and tradition are based on the testimony of the apostles
0.1.2 But the evidence of testimony is always weaker than the evidence of the senses
0.1.3 So, even if scripture and/or tradition tell us that the bread and wine turn into the body and blood of Christ, the evidence of the senses tells us that they remain bread and wine: they have all the sensible properties of bread and wine; nothing more.
0.1.4 Therefore, since the evidence of the senses trumps the evidence of testimony, it is unreasonable to believe in T…

A Priori Naturalism, A Priori Inerrantism, and the Bible

Christian apologists often complain about New Testament critics who bring an a priori rejection of the supernatural to their studies of the New Testament. The underlying rationale, I take it, is that such a presupposition will determine a non-supernatural historical reconstruction of Jesus before they even begin their historical investigations. But if the historical Jesus turns out to be the miracle-working, resurrected Son of God that conservative Christians take him to be, such an assumption will lead them to construct a historically inaccurate conception of Jesus.

I agree with them in this regard: one shouldn't assume what can or can't be true on empirical matters before one even begins one's investigations. Although it's probably unavoidable that we bring assumptions about reality to all of our empirical inquiries, we should hold them tentatively, and allow them to be altered in light of our findings.

Of course, this assumes that supernatural events, if they …

William Lane Craig on the Origin of the Belief in Jesus' Resurrection

I had a brief moment between grading stacks of papers, so I thought I'd make a quick point:

One argument that William Lane Craig uses as a part of his case for Jesus' resurrection can be summarized as follows:

The origin of belief in Jesus' resurrection must have been derived from either Christian sources, Jewish sources, or from experiencing Jesus as risen from the dead. But the belief couldn't have been derived from Christian sources, for Christianity didn't arise until after (or simultaneous with) the belief that he had risen from the dead. Nor could it have been derived from Jewish sources, since the Jews had no concept of a single individual being resurrected prior to the general resurrection at the end of time. Therefore, it must have arisen from experiences that they took to be of a resurrected Jesus.

The argument can be expressed a bit more carefully as follows:

1. If belief in Jesus' resurrection was due to something other than experiences as of Jes…

Problems for the Fine-Tuning Argument

By my lights, the following considerations are sufficient to show that the argument from fine-tuning fails to make theism more likely than not.

There is an equally good, rival explanation of the apparent fine-tuning of our universe. For the fine-tuning for life would be equally well explained if our universe were embedded in a vast “sea” of infinitely many other universes.[1] Imagine a natural process or mechanism that continually generates universes (call it a 'cosmos generator') – perhaps something like a giant quantum field. Each time it pumps out a universe, it gives a random combination of values to its fundamental constants of nature. So on this hypothesis, infinitely many other universes exist – or at least lots and lots – and each one has a different set of values for its fundamental constants. Most of these universes have no life, since only a few possible combinations of values of the constants are life-permitting. But some do (e.g., ours). If so, then the …

Design Arguments: Old and New

The Design Argument

There are two broad forms of the design argument:

1.The Classical (“Old School”) Design Argument:

Paley’s is the most important version of the classical design argument. This version is an argument from analogy. It typically appeals to living organisms and their parts as cases of apparent design. The line of reasoning here can be put as follows:

We come to learn through experience whether an object has been intelligently designed. How do we learn to detect design? Well, over a long course of experience, we notice a constant conjunction of a cause of one type (intelligent designers) producing an effect of a certain type (complex objects whose parts work together to perform a function). Thus, after a while, we no longer have to observe a person designing an object in order to know that the latter has been designed. Rather, we can then legitimately *infer* that, say, a watch was fashioned by an intelligent cause. For we can then justifiably base such an inference …

Outline of the Standard Evangelical Case for the Reliability of the New Testament

I'll probably return to this post a lot to fill in the details and provide explanation, but I just wanted to put something on my blog that provides a way to see the standard case at a glance.

The Reliability of the Orthodox “Portrait” of Jesus according to Evangelicals: The Basic Case[i]

1. From our Current Bibles to the Church Fathers: Textual Criticism
1.1 The Argument from Textual Criticism
1.2 The Argument from Patristic Quotation

“Okay, that gets us back to within a few centuries of the life of Jesus. But how do we know that our information about Jesus wasn’t corrupted prior to that?”

2. From the Church Fathers to the Gospels: The Argument from Patristic Testimony of Apostolic Authorship

“Okay, but the case for apostolic authorship is shaky and widely rejected. Are there other reasons to think that the gospels give us reliable eyewitness testimony about Jesus?”

3. From the Gospels to Their Immediate Sources:
3.1 The Argument from Markan Priority and the Dating of Luke-Acts

Some (Temporarily) Final Thoughts About the Free Will Defense

I'm more than happy to discuss Plantinga's Free Will Defense further with those interested (see previous post), but for now, here's my tentative summary and conclusion on the matter, prefaced with some contextual stage-setting:

A standard way to state the deductive argument from evil is the one we've inherited from Hume in his Dialogues Concerning Natural Religion (who in turn inherited it from Epicurus):

"Is he willing to prevent evil, but not able? then is he impotent. Is he able, but not willing? then is he malevolent. Is he both able and willing? whence then is evil?"

The reasoning here can be teased out as follows:

1. Evil exists. (Premise)
2. If God exists, then God is omnipotent, omniscient, and perfectly good. (Premise)
3. If God is omniscient and omnipotent, then He is able to prevent evil. (Premise)
4. If God is perfectly good, then He is willing to prevent evil. (Premise)
5. If God is willing and able to prevent evil, then evil does not exist. (Premise)

On the Force of "Possibly" in Plantinga's Free Will Defense (Slightly Revised)

Plantinga construes the key claim in his Free Will Defense as possibly true:

(TWD) Possibly, every creaturely essence suffers from transworld depravity.

According to Plantinga, if a creature suffers from transworld depravity, then *every* God-accessible world (i.e., every world *that God can create*)) is one at which the creature goes wrong at least once.

So if some free creature FC is transworld-depraved, then we have:

1) Necessarily, if God actualizes FC, then FC goes wrong at least once.

And if every creature is transworld-depraved, then we have:

2) Necessarily, for any x, if x is a free creature, then if God actualizes x, then x goes wrong at least once.

If so, then if Plantinga is using "possibly" in (TWD) in the metaphysical sense (as in (1)), then (TWD) amounts to:

3) Possibly, it's necessary that for any x, if x is a free creature, then if God actualizes x, then x goes wrong at least once.

But Plantinga accepts S5 modal logic. If so, then he accepts the following axiom…

Intermission: A Quick Point about Plantinga's Free Will Defense

It's often said that Plantinga *refuted* the logical problem of evil -- i.e., that he demonstrated that' there's no logical inconsistency between the existence of an all-knowing, all-powerful, and perfectly good god, on the one hand, and evil on the other. This is extremely misleading. To see why, consider the following three claims, in descending order in terms of strength of claim:

1. The following is a fact: Possibly, every creature that God can create would freely perform at least one morally wrong action.
2. Here is a story that we have decent reason to believe is true: Possibly, every creature that God can create would freely perform at least one morally wrong action.
3. Here is a claim that we can't rule out for sure as false: Possibly, every creature that God can create would freely perform at least one morally wrong action.

Now many apologists talk as though Plantinga has shown that (1) or (2) is true. These are the sorts of claims that Plantinga would have …

A Critique of the Kalam Cosmological Argument

(Note: I've posted this previously at Debunking Christianity.
You can go to the archives at that site and read the follow-up of objections
and replies in the "comments" section below the post)

On the Possibility of a Beginningless Past: A Reply to Craig

William Lane Craig has argued vigorously that, cosmological discoveries aside, it’s reasonable to believe on purely a priori grounds that the set of past events is finite in number.1 He offers two main types of a priori arguments for this claim: (i) that it’s metaphysically impossible for an actually infinite set of concrete things to exist, in which case the set of past events can’t be actually infinite, and (ii) that even if such a set could exist, it’s impossible to traverse it even in principle. Craig doesn’t pursue this claim for it’s own sake, however. Rather, he does so as a means to demonstrating that a theistic god exists. He reasons that if the set of past events is finite, then the universe as a whole had an abs…

Problems for PSR (Slightly Revised)

This post completes my discussion of the deductive cosmological argument from contingency. In my previous post, I considered a set of objections to the argument that didn't seem to be persuasive. The moral of that discussion seemed to be that the argument stands or falls with the viability of PSR.

Here, I offer objections to PSR that seem to have some force. These criticisms aren’t original with me, but rather are standard objections (except perhaps the last one, although it's based on ideas of other authors). Furthermore, I don’t mean to imply that there aren’t other versions of the argument from contingency that may avoid these criticisms. However, they do seem to apply to the variants of the argument that one finds in standard “intermediate-level” apologetics books. The criticisms can be divided into two broad categories: (i) those that undercut the reasons offered for accepting PSR, and (ii) those that indicate that PSR is positively false or unreasonable.

1. Type-…