bookmark_borderG&T Rebuttal, Part 3: Chapter 4

Chapter 4. Divine Design

 
G&T provide a brief introduction to what they call ‘the’ Teleological Argument, which they formulate as follows.
1. Every design had a designer.
2. The universe has a highly complex design.
3. Therefore, the universe had a Designer. (95)
Like the cosmological argument, this argument is deductively valid. Again, my plan is to provide a very brief summary of G&T’s defense of this argument, before providing some critical comments of my own.
(i) Evidence of Design: G&T provide a helpful metaphor with NASA’s Apollo 13 mission to introduce their readers to the basic thrust of their design argument, in which they emphasize the following “anthropic constants”: (1) oxygen level; (2) atmospheric transparency; (3) moon-earth gravitational interaction; (4) carbon dioxide level; and (5) gravity. In order for life to be possible, the value of each constant has to be within a very narrow range. They list ten additional such constants and then refer to astrophysicist Hugh Ross, who has identified a total of 122 such constants.
How does this constitute evidence of design? First, G&T argue that if any of the anthropic constants had a value outside of a very narrow range, life would have been impossible. Next, they ask us to imagine lots of different possible universes, each with different values of the anthropic constants. If we compare the number of life-permitting universes to the number of possible universes, we will find that only a small portion of the possible universes are life-permitting.  Indeed, summarizing Ross’s calculations, G&T report that the probability that all 122 of these constants would have life-permitting values for any planet in the universe by chance is 1 in 10138.
(ii) Atheistic Objections: G&T then consider atheistic responses to this argument: (1) an admission of a Designer; (2) chance (in the form of the Multiple Universe or multiverse hypothesis). After presenting a series of objections to the multiverse hypothesis, G&T triumphantly conclude that the anthropic principle shows “beyond a reasonable doubt” that the universe is designed (111). Furthermore, they claim that atheists who remain atheists in the face of this design argument are irrational and unwilling to admit there is a designer (112).
(iii) Some Critical Comments: Having now outlined the case which G&T make for divine design, I shall now make some critical comments.  As will become clear from my comments, I think that G&T only considered the weakest objections to their argument.
(a) Question-begging: First, G&T’s version of the teleological argument is a petitio principii, viz., it begs the question.[1] Why do G&T not consider the possibility that the universe’s life-permitting conditions are the result of impersonal, mechanistic causes? Because they rule out that possibility in advance. G&T can conclude “the universe has a highly complex design” only by assuming that the universe’s life-permitting conditions had a Designer. But G&T also claim that the design argument is supposed to lead to the conclusion that the universe had a Designer. The presupposition that the universe had a Designer is both an assumption and a conclusion of G&T’s design argument. This vicious circularity nullifies their argument in its present form.
In order to repair the argument, G&T would have to rely upon non-question-begging premises. For example, let’s start with the statement about the “anthropic constants.” Then the first premise of the repaired argument can be written as follows.

1’. We know that only a small portion of the range of possible values that the anthropic constants could have had would be life permitting.

Next, we need to add a statement about how theism “predicts” the cosmic design data better than atheism.

2’. The fact that the anthropic constants have life permitting values is much more probable on the assumption that God exists than on the assumption that God does not exist.

Finally, we conclude with a statement about the direction and weight of the evidence.

3’. The fact that the anthropic constants have life permitting values is strong evidence for the existence of God.

Although G&T don’t explicitly appeal to 1’-3’, I trust that even they would agree that their version of the design argument depends upon the truth of all three statements. Furthermore, unlike G&T’s version, this design argument doesn’t beg the question. Finally, this repaired argument is useful because its premises clarify some of the key disputes between proponents and critics of this type of design argument. This leads to my next point.
(b) G&T Understate the Evidence: Even if we assume that so-called cosmic “fine-tuning” is evidence favoring theism over naturalism, that argument commits the fallacy of understated evidence.[2]  In other words, even if the general fact of fine-tuning is more probable on the assumption that theism is true than on the assumption that naturalism is true, it ignores other, more specific facts about fine-tuning, facts that, given fine-tuning, are more likely on naturalism than on theism.
What are these other facts?
(1) So much of the universe is highly hostile to life. Most of the universe is incredibly hostile to life, such as containing vast amounts of empty space, temperatures near absolute zero, cosmic radiation, and so forth. Given that intelligent life of some sort exists in some universe, the fact that so much of our universe is highly hostile to life is more probable on naturalism than it is on theism.[3]
(2) Our universe is not teeming with life, including life much more impressive than human life. Given that intelligent life of some sort exists in some universe, the fact that our universe is not known to have relatively more impressive life is much more probable on single-universe naturalism than it is on theism.[4]
(3) The only intelligent life we know of is human. Given that intelligent life of some sort exists in the universe, the fact that the only intelligent life we know of is human is very many times more probable on naturalism than it is on theism.[5]
(4) Intelligent life is the result of evolution. G&T dispute the fact of biological evolution, so we will address their objections later.  For now we will simply note the following. Given that intelligent life of some sort exists in some universe, the fact that it developed as a result of biological evolution (if it is a fact) is more probable on naturalism than on it is on theism.[6]
The upshot is this. Even if the general fact of cosmic “fine-tuning” were more probable on theism than on naturalism, there are other, more specific facts about cosmic “fine-tuning,” facts that, given cosmic “fine-tuning,” are more likely on naturalism than on theism. Once all of the evidence about cosmic “fine-tuning” has been fully stated, however, it’s far from obvious that facts about cosmic “fine-tuning” favor theism over naturalism.
(c) Completely Arbitrary Probability Estimates: Recall that G&T appeal to Ross’s probability estimates in order to show that the probability of 122 anthropic constants having life-permitting values is 1 in 10138.[7] Ross arrives at this ridiculously low number, in part, from multiplying together his estimates of the probabilities for each anthropic constant or parameter. Consider, for example, the relative abundances of different exotic mass particles. Ross estimates that the probability of that parameter having a life-permitting value is 0.1.
But there are two problems with Ross’s methodology. First, Ross doesn’t describe the range of possible values for each parameter or, more important, the subset of such values which would be life-permitting (even if we grant the bogus assumption that life as we know it is the only possible kind of life). In the absence of such a range, it’s hard to independently test his probability estimates.
Second, if these probability estimates are subjective probabilities—and that’s unclear—then Ross provides no justification for accepting them. The problem is not that they are subjective probabilities per se. The use of subjective probabilities can be justified if (a) the estimator is calibrated; and (b) there are no equally competent authorities who disagree. Rather, the problem is that Ross provides no evidence that his estimates of his own uncertainty are “calibrated,” i.e., that he consistently avoids a bias towards overconfidence or underconfidence when estimating subjective probabilities.[8] Without a reason to believe that Ross is a calibrated estimator, we have no reason to put any credence into his estimates. And it’s highly probable that Ross is not a calibrated estimator, for the simple reason that calibration training teaches subject matter experts to estimate a range of numerical values, rather than providing point estimates such as those provided by Ross.
(d) Varying the Constants but Fixing the Physics: G&T’s argument depends upon counting the number of possible universes with different values for the anthropic constants but with the same laws of physics. But why restrict the set of possible universes to only those with the same laws of physics? Why not also include possible universes with different physics? Bradley Monton makes this point extremely well; it’s worth quoting him at length.

The general point is as follows: when faced with the fine-tuning evidence, it is reasonable to not be surprised. We already knew that there are many possible universes that are not life-permitting, and yet are similar in certain ways to our actual universe. The fine-tuning argument encourages us to focus our attention on those possible universes that have the same laws of physics as ours, but different fundamental constants. But why not focus on those possible universes that have the same types of particles as ours, but different fundamental laws? Or why not focus on those possible universes that have the same density distribution as ours, but different types of particles? Before I was faced with the fine-tuning evidence, I already knew that our universe was special, in the sense that there are many possible universes similar to ours in certain ways and yet not life-permitting. I already knew that, if God existed, God would have to choose to actualize our life-permitting universe from among a sea of similar non-life-permitting universes. I already knew that, if God did not exist, there’s a sense in which we are lucky that the universe is life-permitting—there are many possible universes similar to ours which are not. The fine-tuning evidence doesn’t change any of that, and hence the fine-tuning evidence doesn’t change my probability for the existence of God.[9]

The upshot is that if our goal is to count the relative frequency of life-permitting universes among all possible universes, then we have to consider all possible universes, not just those with the same laws of physics. Since neither G&T nor Ross have done that, it follows that their defense of this crucial premise (and hence their design argument as a whole) is, at best, incomplete.
(e) The (Im)probability of Fine-Tuning on Theism: Consider an analogy. Let E be the evidence that I rolled a four when rolling a fair six-sided die; geocentrism (G) be the hypothesis that the earth is the center of the solar system; and heliocentrism (H) be the hypothesis that the sun is the center of the solar system. H gives us virtually no reason at all to expect that I would roll a four. In fact, based upon our background knowledge (B) about fair dice, we would predict that I did not roll a four. In other words, H and B combined predict not E (~E). But this would be a horrible reason for saying that E favors G & B over H & B. Why? G and B combined also predict ~E. So there’s no reason at all to think my rolling a four is more probable on G than on H. But then it follows that there’s no reason to think my rolling a four is evidence favoring G over H.
This same point applies to G&T’s design argument. In order to show that the anthropic constants (or any other potential evidence) favor theism over atheism, one has to do more than show that the data is improbable on atheism. One also has to show that (i) theism predicts the data while atheism does not; (ii) atheism predicts the non-existence of the data while theism does not; or (c) that the data is more probable on theism than on atheism.  Otherwise, by definition, there is literally no reason at all to believe that the data is evidence favoring theism over atheism. With that in mind, then, we may ask the following question. What reason do G&T offer for thinking that the anthropic constants are more probable on theism than on atheism? So far as I can tell, the answer is, “None whatsoever.”
Furthermore, it’s far from obvious that the anthropic constants are more probable on theism than on atheism. As G&T explain, theism is the belief that “a personal God who created the universe but is not part of the universe” (22). On the assumption that theism is true, it’s far from obvious that God would fine-tune a physical universe for life. In fact, this is still far from obvious even if we assume that God wants to create other minds besides his own, which is itself a debatable assumption. Even if God wants to create other minds besides his own, why should we assume that He would want to create embodied minds rather than just immaterial souls or spirits? G&T never say; in fact, G&T don’t even consider the question. This is yet another reason why G&T’s design argument is, at best, incomplete.

Rebuttal to Geisler’s and Turek’s “I Don’t Have Enough Faith to be an Atheist”

Notes
[1] David Hume, Dialogues Concerning Natural Religion: Edited and with Commentary by Nelson Pike (Indianapolis, Bobbs-Merill, 1970); Antony Flew, “Arguments to Design” The Secular Web (1996), http://infidels.org/library/modern/antony_flew/design.html. I am grateful to Robert Greg Cavin for bringing Nelson Pike’s commentary to my attention.
[2] Paul Draper, “Collins’ Case for Cosmic Design” The Great Debate (2008), http://infidels.org/library/modern/paul_draper/no-design.html.
[3] Jeffery Jay Lowder, “Hostility of the Universe to Life: Understated Evidence about Cosmic Fine-Tuning?” The Secular Outpost (January 22, 2013), https://secularfrontier.infidels.org/2013/01/22/hostility-of-the-universe-to-life-understated-evidence-about-cosmic-fine-tuning/.
[4] Draper 2008.
[5] Draper 2008.
[6] Draper 2008.
[7] Incidentally, intelligent design theorist William Dembski has argued that any event with a probability less than 1 in 10150 can be expected to happen by chance alone during the lifetime of our universe. If Dembski is correct, then this point may undermine the significance of Ross’ probability estimates. But I do not wish to place any emphasis on this point since I was unable to analyze Dembski’s argument before finishing this review. Interested readers may wish to consult William A. Dembski, No Free Lunch: Why Specified Complexity Cannot Be Purchased Without Intelligence (Lanham: Rowman & Littlefield,m 2002). Thanks to Richard Carrier for making me aware of this point.
[8] Douglas W. Hubbard, How to Measure Anything: Finding the Value of Intangibles in Business (3rd ed., New York: Wiley, 2014).
[9] Bradley Monton, “God, Fine-Tuning, and the Problem of Old Evidence” British Journal for the Philosophy of Science 57 (2006): 405-424 at 420-21. Italics are mine.

bookmark_borderSwinburne’s Cosmological and Teleological Arguments – Part 3

I am exploring a concern about, or potential objection to, Swinburne’s inductive cosmological and teleological arguments for the existence of God. The objection I have in mind is something like this, for the cosmological argument:
Although the one factual premise of Swinburne’s cosmological argument is supposed to be the ONLY contingent factual claim or assumption upon which the conclusion of the argument rests, the argument actually rests on a considerable number and variety of contingent factual claims and assumptions, and this casts some reasonable doubt on the argument.
In order to explore this potential objection in a somewhat systematic way, I have made an outline of the general kinds of objections that are made against arguments. An argument has three basic parts (a premise or premises, an inference, and a conclusion). Thus, there are three basic types of objection:
TYPES OF OBJECTION
1. Objection to a premise of the argument (false, dubious, unclear, ambiguous, unknowable)
2. Objection to an inference of the argument (illogical, invalid, dubious, weak)

3. Objection to the conclusion of the argument (false, dubious, unclear, ambiguous, unknowable)

Since an objection is itself an argument, replies to objections are also objections to an argument, and thus there are at least three types of reply:
TYPES OF REPLY TO AN OBJECTION
1. Objection to a premise of the objection (false, dubious, unclear, ambiguous, unknowable)
2. Objection to an inference of the objection (illogical, invalid, dubious, weak)
3. Objection to the conclusion of the objection (false, dubious, unclear, ambiguous, unknowable)
Also, in presenting or developing an argument, one can provide support for any of the three basic parts of an argument: support for a premise, support for an inference, and support for the conclusion. If one gives evidence in support of the truth of the conclusion, however, that amounts to giving another argument or piece of evidence in addition to the original argument.
So, where might contingent factual claims be called up by Swinburne in a discussion about the cosmological argument (TCA)? He might put forward some contingent factual claims in support of the truth of the premise of his argument, or in support of the inference in this argument, or in support of the clarity or knowability of the conclusion of the argument (but not in support of the truth of the conclusion, because that would introduce a whole new argument into the picture).
Like any good philosopher, Swinburne also considers objections to his arguments, so he might put forward some contingent factual claims in response to an objection to the premise of his cosmological argument, or in response to an objection to the inference of his cosmological argument, or in response to an objection to the conclusion of his argument. Here then are the key questions to examine:
1. Does Swinburne use contingent factual claims/assumptions to support the premise of TCA?
2. Does Swinburne use contingent factual claims/assumptions to support the inference in TCA?
3. Does Swinburne use contingent factual claims/assumptions to support the conclusion of TCA (in terms of clarity or knowability)?
4. Does Swinburne use contingent factual claims/assumptions to reply to an objection to the premise of TCA?
5. Does Swinburne use contingent factual claims/assumptions to reply to an objection to the inference in TCA?
6. Does Swinburne use contingent factual claims/assumptions to reply to an objection to the conclusion of TCA?
If Swinburne does use contingent factual claims for any of these purposes, then this would provide some confirmation of my suspicion about his cosmological and teleological arguments. However, one further question would also need to be answered to fully confirm my suspicion: Is Swinburne’s use of contingent factual claims (other than the one premise of TCA) essential to supporting or defending this argument? or is there some other way to support or defend the point in question without use of contingent factual claims, by using only a priori truths, analytic truths, or tautological truths?

bookmark_borderSwinburne’s Cosmological and Teleological Arguments – Part 2

Like many other liberals, I’m delighted and mesmerized by Bridgegate and various other Chris Christie scandals from the fine state of New Jersey. I cannot wait for my daily dose of Rachel Maddow dishing the latest dirt on Christie and his idiotic crowd of corrupt New Jersey hooligans.
What does this have to do with Swinburne’s arguments for God? Well, one neat trick that a couple of Christie’s friends have pulled is to plead the 5th amendment as a legal justification for refusing to turn over documents in accordance with subpoenas from the N.J. legislature. I initially thought it was ridiculous to plead the 5th in relation to providing documents, but a recent Supreme Court case did apply the 5th amendment to the production of documents, and after reading a bit about that case, I see that pleading the 5th makes a good deal of sense in this particular case. The key concepts here are ‘relevance’ and ‘background knowledge’, and these concepts also apply, quite appropriately, to Swinburne’s case for God.
The subpoenas issued by the N.J. legislature basically request documents that are RELEVANT to Bridgegate, relevant to the lane closures on the George Washington Bridge back in September of last year. But judgments of relevance always depend on BACKGROUND KNOWLEDGE. Some documents are such that anyone, with common background knowledge could identify the document as being relevant. For example, if an email says “Should we plan the lane closures on the George Washington bridge for early in September?” just about anyone could determine that email to be relevant to the inquiry of the legislature.
But the relevance of some documents might not be so obvious. For example, the famous email from Bridget Anne Kelly, then Christie’s deputy chief of staff, reads: “Time for some traffic problems in Fort Lee”. Notice that this email does NOT explicitly reference the George Washington bridge. Nor does it say anything about closing down lanes on a bridge. Someone (i.e. David Wildstein) had some background knowledge about the context of this email, such that the few words in the email are interpreted as being relevant to the lane closures on the George Washington bridge back in September.
Roughly speaking, Wildstein knew that he and Bridget Kelly were part of a criminal conspiracy to create a terrible traffic jam in Fort Lee by shutting down lanes on the George Washington bridge. This background knowledge allowed Wildstein to identify that email as being part of a collection of conversations and discussions and planning sessions in this criminal conspiracy.
In putting forward this specific email as being relevant to the lane closures on the George Washington bridge, Wildstein is revealing some of his own background knowledge, and thus he was, in effect, testifying against himself. It is not just the fact that the contents of the email constitute potential evidence for criminal charges against him, but the very production of this email amounts to him testifying that the email is relevant, which appears to imply that Wildstein has background knowledge of a criminal conspiracy.
In any case, whether or not you agree with my take on the Bridget Kelly email, it is clear that judgments of relevance are based upon one’s background knowledge. The same goes for judgments of significance. These concepts and related principles can be applied to Swinburne’s case for God, and to his inductive Cosmological and Teleological arguments. Each inductive argument for God involves a single factual premise, which Swinburne claims to provide inductive evidence for the existence of God.
My objection or my concern with these arguments (at least the concern I wish to explore here and now) is that in order to properly and correctly understand the meaning, the relevance, and the significance of each of those premises, one must draw on a significant amount of contingent factual background knowledge. If I am correct in this view, then that opens the door to a significant degree of doubt about the correctness and strength of these arguments, because if they actually depend on a larger set of factual assumptions (which might either contain some false or questionable claims, or which might reflect a biased selection from a larger collection of available and relevant factual evidence), then there is clearly a sense that the significance or strength of these arguments is not a purely a priori matter, and is subject to reasonable doubts and challenges.
One thing I admire about Swinburne is that he not only studied philosophy of religion and theology, but he understood the importance of science, especially as a perceived threat to religious belief, and so he also studied philosophy of science and the history of science, and he spent several years thinking about and writing about the philosophy of science prior to building his case for God. In his book, The Existence of God, Swinburne puts his knowledge of science to good use, and this is especially the case with the presentation of his inductive cosmological and teleological arguments.
My concern is that much of the background knowledge that Swinburne brings to bear concerning these arguments are contingent factual assumptions/beliefs, in which case, it appears that it is mistaken or misleading to view these arguments as consisting of just one or two contingent factual claims, as opposed to them being based on a large collection of contingent factual assumptions, some of which might be false or questionable, and which may be the result of a biased selection of such contingent ‘facts’ from a much broader collection of evidence (which may include facts that don’t fit so well with Swinburne’s theism).
Swinburne’s inductive cosmological argument has just one premise (see EOG, p.149):
e. A complex physical universe exists (over a period of time).
And it has a single simple conclusion:
g. God exists.
Swinburne argues that this contingent factual claim is both relevant and significant in relation to the hypothesis that ‘God exists’. These judgments, I believe, are based on Swinburne’s knowledge (and beliefs) about physics, chemistry, astronomy, cosmology, philosophy of science, and history of science. I suspect that there is a great deal of contingent background knowledge (or beliefs) that is being drawn upon not only in the formulation of Swinburne’s own judgment that e is relevant and significant in relation to g, but that in order to argue this point, in order to persuade others of his view on this matter, Swinburne must draw upon a large collection of contingent background knowledge (or beliefs).
It is the degree of complexity of the physical universe that impresses Swinburne, but the expression “a complex physical universe” is somewhat vague. How complex does a universe have to be in order for e to be true? If only a small degree of complexity is required for this expression to be correctly applied, then perhaps the evidence here is of only minor significance or weight. Also, we need to have some way to measure or quantify degree of complexity.
Could the existence of a single electron count as the existence of “a complex physical universe”? That seems a bit too simple to me, but if the behavior or nature of the electron was determined by several laws of physics, perhaps even a single electron could count as “a complex physical universe”. If so, then e would not be very significant, it seems to me, as evidence for theism.
Part of Swinburne’s discussion and defense of his inductive cosmological argument appears to revolve around a possible objection. The objection could be put like this:
It does seem fantastically improbable that complex organisms such as tigers, dolphins, and human beings would spontaneously arise as the result of a chance conglomeration of inorganic matter. But according to the well-established theory of evolution, such complex organisms did not arise in such a manner. Rather, very simple organisms were formed by chance conglomeration of organic compounds, and over billions of years through the process of evolution very complex organisms arose from less complex organisms which in turn arose from very simple original life forms. The complex physical universe that we observe today might also have arisen through a process of development from a much simpler physical universe.
Swinburne thinks this is not just merely a possibility or conjecture; he thinks this is probably the way the present physical universe came to be what it is today:
…all the evidence suggests that the universe evolved from a much simpler state in accord with the laws of nature ensuring that such a universe would develop into a large complex universe. (EOG, p.150)
Knowledge about the process of biological evolution is mostly contingent factual knowledge, not knowledge of tautological truths. This knowledge of biological evolution suggests the possibility that the current complexity of the physical universe might also have arisen through some natural process over a long period of time, and that billions of years ago, the universe might have been much more simple, much less complex, than it is now. But this objection does NOT require contingent factual knowledge. The main idea here is of a concept or a logical possibility: something complex can arise from something much simpler through natural processes. Such an idea or possibility could occur to someone who had no knowledge of the biological process of evolution. Though the well-established theory of evolution gives this idea or possibility some initial plausibility and appeal, the idea can stand on its own, at least as a possibility that needs to be considered, and taken seriously.
However, if we take this idea, this logical possibility, seriously it seems to me that the objection this raises against Swinburne’s cosmological argument can be properly evaluated only in terms of contingent factual background knowledge about: physics, chemistry, biology, evolution, astronomy, cosmology, philosophy of science, and history of science. Furthermore, it seems to me that Swinburne’s response to this objection draws upon his knowledge of physics, chemistry, astronomy, cosmology, etc. In order to persuade others that his inductive Cosmological argument is significant and can withstand this objection, Swinburne must make use of his considerable stock of contingent scientific knowledge (or beliefs).
To be continued…

bookmark_borderSwinburne’s Cosmological & Teleological Arguments

I’m not going to try to fully explain and evaluate Swinburne’s Cosmological and Teleological arguments for God here. That would be way too much to tackle in one or two blog posts. There are just a couple of doubts or concerns about these arguments that I would like to express and explore.
Swinburne’s inductive cosmological argument for God has just one premise:
e. A complex physical universe exists (over a period of time).
Therefore:
g. God exists.

Swinburne argues that e is more likely to be the case if God exists, than if God does NOT exist. From this he concludes that the e represents legitimate inductive evidence for the existence of God; that is to say, the truth of e increases the probability that God exists relative to the a priori probability that God exists, relative to the probability that God exist given only tautological truths (truths of logic and math and analytic conceptual truths) as background knowledge.
If g represents the hypothesis that God exists, and k represents background knowledge consisting only of tautological truths, then Swinburne argues for the following claim:
1. P(e|g & k) > P(e|k)
(Read this as asserting: “The probability of e given g and k is GREATER THAN the probability of e given only k.”)
From premise (1), Swinburne infers the following:
2. P(g|e & k) > P(g|k)
(Read this as asserting: “The probability of g given e and k is GREATER THAN the probability of g given only k.”)
One objection that has been raised against this argument is that it is not clear that a probability can be reasonably or justifiably assigned to a factual hypothesis given background knowledge consisting in only tautological truths. If “The probability of e given only k” cannot be reasonably or justifiably determined (or estimated), then we are in no position assert that some other probability is greater than (or less than, or equivalent to) “The probability of e given only k”.
The same issue arises with claim (2) that Swinburne infers from claim (1). If “The probability of g given only k” cannot be reasonably or justifiably determined, then we are in no position to assert that some other probability is greater than (or less than, or equivalent to) “The probability of g given only k”.
But this issue with the idea of a probability given only background knowledge consisting of tautological truths is not the concern I wish to explore here. My concern is with the other conditional probabilities in these equations:
P(e| g & k)
P(g| e & k)
I’m not sure that these probabilities make sense either. My concern is this: Is it possible to know just one contingent fact? Is it possible to know that ‘God exists’ without knowing any other contingent facts? Is it possible to know that ‘A complex physical universe exists (for a period of time)’ without knowing any other contingent facts? If it is not possible to know just one contingent fact, or if it is not possible to know only the contingent fact that ‘God exists’ or to know only the contingent fact that ‘A complex physical universe exists (for a period of time)’, then it appears that we are being asked to conceive of a set of circumstances that is logically impossible.
If it is not possible for a human being to know just one contingent fact, these expressions might still be meaningful and useful as abstractions, as tools of hypothetical reasoning. Arguments typically have just a few premises, and we evaluate arguments by focusing in on these questions: Are each of the premises clear and unambiguous? Are each of the premises true? If all of the premises were true, would the conclusion follow logically? or would the conclusion be made probable assuming the premises were true? Does any of the premises beg the question at issue?
However, if knowing that g is true requires that one knows some other things as well, if knowing g presupposes knowing q, then objections to the knowability of q also work as objections to the knowability of g. So, the epistemological presuppositions of knowing g or of knowing e are relevant to evaluating Swinburne’s cosmological argument.
Suppose I know the fact that I am 5 feet 8 inches tall. Suppose I know that ‘Brad Bowen is 5 feet 8 inches tall’. Can I know just this contingent fact and no other contingent facts? Let’s think about this for a bit. I must understand that the name ‘Brad Bowen’ refers to a specific person, a specific human being, and that the measurement here relates to the size of the human body that belongs to a specific human being. I suppose that all of this could be taken as conceptual knowledge, as knowledge involved in simply understanding the meanings of the words and phrases in the sentence ‘Brad Bowen is 5 feet 8 inches tall’.
To have a clear and correct understanding of this sentence, I must also know that while many animals walk on four legs, human beings walk on two legs and use their arms for other purposes. Thus, the height of a human being is not measured when the person is on his or her hands and knees. Also, height at least for human beings, is measured when the person is standing, not when the person is horizontal, as when the person is sleeping. I should also know that rulers or yardsticks or measuring tapes are used for measuring the height of humans. This assumes that there are physical substances that are fairly stable in their length. Rulers and yardsticks don’t generally grow or shrink large amounts in short periods of time. A ruler that is 12 inches this morning is not likely to be 24 inches this evening. A yardstick that is 36 inches today is not likely to be 25 feet tomorrow. Furthermore, human height is significant and relevant in part because it is relatively stable, at least for periods of days and weeks. I was only about two feet tall when I was born, was about four feet tall when in elementary school, and was over five feet tall in high school. People usually get taller rapidly as young children and teenagers, and then their growth in height slows, and height is stable for many years.
As you can see, there is a fair amount of background knowledge involved in knowing the fact that ‘Brad Bowen is 5 feet 8 inches tall’. Some of that knowledge is conceptual/linguistic knowledge, but some of the knowledge mentioned above is contingent factual knowledge about the world and about human beings. If such an apparently simple and innocuous fact as this requires a good deal of background knowledge in order to clearly and fully understand and know the fact to be true, then I suspect that a deep philosophical claim like ‘God exists’ or ‘A complex physical universe exists’ also requires a significant amount of background knowledge to clearly and fully understand that claim.
To be continued…