Brains and digital computers go about computation in very different ways—so different, in fact, that it’s less than clear to me that “computation” (in the Turing machine sense) is what brains are really doing. This probably accounts for why trivial brain tasks like detecting speech, understanding natural language, and recognizing faces are at present next to impossible to do well in software, as anyone who has tried to use their mobile phone’s voice activated dialing can attest.

Researchers at Stanford are onto this:

Now Kwabena Boahen, a neuroengineer at Stanford University, is planning the most ambitious neuromorphic project to date: creating a silicon model of the cortex. The first-generation design will be composed of a circuit board with 16 chips, each containing a 256-by-256 array of silicon neurons. Groups of neurons can be set to have different electrical properties, mimicking different types of cells in the cortex. Engineers can also program specific connections between the cells to model the architecture in different parts of the cortex.

Substance dualists should be happy about this kind of research for two reasons. First, if it works, it is likely to yield new tools of heretofore unheard-of levels of aweXomeness. For instance, right now Google image search offers up pictures of trees based on the close association of a web image with text that talks about generally arboreal things. With massively scalable brain-like image recognition, maybe we’ll be able to do web-scale searches for pictures of, say, tire swings with foreboding skies in the background. But then physicalists get jazzed about this kind of thing too.

The real payoff for substance dualists is in the utterly faithful simulation of the human brain. That this will be done someday is a certainty. And theories of quantum consciousness notwithstanding, the brain is a machine—an elaborate configuration of matter scrupulously obeying the laws of physics. If substance dualism is true, then the silicon brain should be qualitatively different from the human one. It might be able to associate visual images with one another, find subtle patterns in search spaces, and carry on a spoken conversation with a person, but we would predict that its soulless-ness will in some way be obvious. Kind of like when Dr. Kurnow asked SAL in 2010 how she felt about being powered down: the question made no sense to her. Enfleshed souls tend to be a bit touchier about that one.

I have long thought it a key aspect of the Classical school that we always have our apologetic money on the table. Hence if the brain is the organ of the mind, then as technology allows, let’s build a replica brain and have a talk with it. If it’s indistinguishable from a person, I lose a line of evidence. If, the better and better we get at making silicon brains, the more and more obvious it is that these things are not human, then we need to have a nice, long talk about just how silly it is for me to believe that I have an immaterial component that is essential to my identity.

The metaphysics of the human person notwithstanding, it just wouldn’t fun if they didn’t create some nice, new bioethical dilemmas while they were at it:

Engineers ultimately hope to use the information generated by the silicon cortex in a variety of ways–to build better neural prosthesis, for example. “The real-time aspect of this technology allows us in principle to interface the silicon cortex with the real cortex or brain,” says Gert Cauwenberghs, a neuroengineer at the University of California, San Diego. “There is the promise, at least in the future, to build a prosthesis to replace some lost motor function or sensory function.”

And I’m sure it will stop there. William Gibson, call your office.

h/t Slashdot

Josephy Cooney has written about avoiding the unfortunate “Developer UI” condition painfully known to software developers and users alike. His post focuses more on development process and the ad-hoc methods that can allow hastily conceived developer utilities to become a permanent part of shipping products. He gives some guidelines to help programmers avoid creating overly cumbersome user interface elements for their own strictly utilitarian purposes, lest these things grow malformed legs and end up half-ambulating around the application forever.

My own struggles with Developer UI are a bit different: I find that managing a group of only developers—myself included for our purposes here—makes user interface design difficult. We never have a problem exposing cobbled-together utility code and having people fall in love with it, but we do have fairly typical problems doing good interaction design, being too small of a shop to have a specialist UI designer on the payroll.

The problem is that good developers are trained to take the bewildering array of particulars in their problem domain and abstract them and systematize them into something simple and elegant. (Another good, if indirect, reason for developers to be realists: universals are your stock in trade.) This, combined with the typical developer bias towards utility over beauty, can create some pretty cumbersome human interfaces. My typical first pass will result in a UI that is beautifully abstracted to expose the deepest conceptual core components of the system in such a way as to be completely inaccessible to any normal person who has not thought about the product for as long as I have. Which is to say pretty much everybody else in the world is going to think it’s trash.

The trick is to design user interfaces to work in a way that most people will expect, rather than the way a developer would calculate. The application model—the view of the world exposed by the program, plus its relevant data—ought to coincide with the user model, or the view of the world and its relevant data that is natively and unreflectively assumed by the user. Hence deep knowledge of the application’s internal model is a huge barrier to effective UI design; it is a vast body of facts and mental habits which must nearly be forgotten in order to get oneself into the user’s mind and make a good guess about the model residing there. This involves some disciplines which, while not in any way antithetical to software development, are not really rewarded in the field either: things like the ability to see things through eyes that are very different from your own or the ability to step back, blur your vision, and get a good view of the big picture.

It’s like being a camera that can switch effortlessly between a macro lens and a fisheye lens. Anyone who can do this well has a shot at creating outstanding software which is both easy and pleasurable to use—which should be the among the highest aspirations of people in this profession. If you can only manage one of those lenses, you’re either stuck in a cube writing code or in a marketing department being enthusiastic for the rest of your career. Not that there’s anything wrong with that, as Seinfeld said, but it’s nice to aim higher.

h/t Style Gala

For my metaphysics term paper, I originally sought out to answer the question of whether I, as a software engineer, actually create something. Some dreary economic Eyores like to hang their heads over the fact that manufacturing of “real things” has fled the United States in favor of various less-real things (pizza delivery, information, management, etc.), and it strikes me as something of a personal affront that my work results in nonexistent things. Moreover, the nominalist view that my work results merely in magnetic particles oriented in just-so configurations on metal platters, or in small holes burned just-so in plastic discs, is also no way to comfort oneself with the significance of one’s life work during the dark watches of the night.

Well, the idea drifed a little bit. That question is really about the ontology of software, which turns out to be a different thing from information. Software is intimately tied up with computational theory, whose ontological destiny is conjoined to the metaphysics of mathematics, partcuarly (I think) of Universal Turning Machines. At least this seems like a good direction to take were one to strike out on this analysis afresh. However, this is not the paper I wrote.

Seeking to be faithful to my title rather than my original career-justifying impluse, I stuck with analyzing information itself. Enjoy the paper. If my conclusion surprises you, please know that I share your company; I really didn’t know where things would go when I began, and I was surprised to find where they ended up. I think my analysis of the transmission and storage of information is still somewhat weak, but for now I will stand by the overall conclusion the paper reaches. Enjoy.

On the Ontology of Information (61kB)

Abstract entities are things like numbers, classes, relations, and colors which are real existents having no spatiotemporal presence. It might better comport with the contemporary philosophical zeitgeist to identify abstract entities with mental states (if not mere brain states!), but this approach is less than satisfactory. My idea of Boltzmann’s constant is irreparably a first-person phenomenon, as is my hypothetical interlocutor’s idea of the same, but the number itself is clearly not captive to first-person status. The account of how ideas can be mediated between minds falls victim to an infinite regress if ideas do not at some point refer to a third-person object. Moreover, ideas qua ideas have the property of belonging to the mind holding them, but physical constants lack this property; therefore, they cannot be identical to their mental conception. The same applies to other abstract entities.

Thus abstract entities can be considered to be real objects to which the identity relation applies but which are not individuated in space-time and are not themselves minds. (Minds may be a kind of individual thing which is not abstract and not spatiotemporal, but space forbids a treatment of this case here.) Each abstract object is the locus of a given set of properties, and so can be said to possess essence or whatness. Each can be identified by some description or definition (e.g., that proposition which is expressed by the English sentence “Blancmange is white”), and so can be said to possess individuation or thatness. Their thatness is of a qualitatively different kind than that of concrete minds and spatiotemporal objects, which cases may call for differing accounts of individuation.

A fictitious object, or fiction, is a kind of abstract entity that originates in the mind of an author. Its essential properties, or its whatness, are determined by the author and can be mediated to readers’ minds linguistically. Its thatness obtains only in the minds of the author and the reader, and not in the real state of affairs.

Yet fictions are not to be identified with ideas or conceptions. It is true that I must have a conception of Trogdor the Burninator in order to think about him, but this approach may again create an infinite regress, since if I need an idea of Trogdor to think about him, I also need an idea of my idea of Trogdor to have my idea of Trogdor. Furthermore, this requirement is no less true of non-fictional, concrete, spatiotemporal objects like the Graber Administration Building.

Also, fictions are counterfactual, but must be conceivable; inconceivable objects may not participate in existence in any sense. The legendary Square Circle of Bow Mar may be claimed to be gilded and thirteen stone in weight, but the mythic device cannot be said to exist even abstractly, since it cannot be meaningfully conceived. A non-contradictory fiction, like a pro-life Democrat elected to national office, is not similarly disadvantaged, but to qualify as fictional it necessarily does not obtain in the real state of affairs.

Suarez identifies three kinds of distinctions: real, mental, and modal. Real distinctions hold between things which have their own independent existence and can endure separation from each other without either thing ceasing to exist. Mental distinctions hold between things which are not actually distinct, but are only thought of as such because of incomplete mental concepts or ideas. Suarez introduces the concept of modality to address those distinctions which really exist but which cannot endure separation without one of the distinguished things ceasing to exist. Modal distinctions fill a key role in rationalizing identity.

Modes are not distinct things or entities in themselves. Rather, they are necessarily conjoined to and cannot possibly exist without the prior existence of the thing of which they are modes. They modify the thing to which they are attached, conferring some property to it which would not otherwise have adhered in the object, but they do not in adhering create any new object.

An example might be helpful. To begin with, assume that the independent existence of universals like “blackness” or “being oriented towards the cause of global justice” has been established by prior argumentation. Blackness really exists and is really distinct from, say, whiteness, but it is an abstract object, having no spacio-temporal existence in any conceivable state of affairs. When blackness finds instantiation in a distinct object like a U2 Special Edition iPod, the device’s black color is said to be a mode of the object. The existing object is modified by the adherence of the universal color in the particular MP3 player, but no new object called “iPod-black” or “this iPod’s black color” is created—thus no real distinction exists between black and iPod. The black color—not Blackness Itself, but this black in this object—is modally distinct from the iPod.

Modal distinctions contribute to our understanding of identity by providing a framework for understanding how universal properties can inhere in particular objects. If we wish to consider the identity of the object we hold to be our iPod, we would of course wish to keep our reflections as simple as possible without multiplying needlessly the entities under consideration. We would not want, upon realizing that our iPod looks black, to divorce “black” from “iPod” and christen the color a new object to be identified. Not only would identity quickly become an unapproachable jumble of concepts (portable MP3 player, hard, shiny, U2-endorsed, etc.), but it would not be clear how properties could possibly inhere in the object under consideration. If each property were a distinct object in itself, we would find ourselves bereft of any means of claiming that the iPod actually held properties; instead it would have some dubious relation to independent objects like “black” or “having been signed by The Edge.” However, if we hold properties to be modes of the object, the object’s identity becomes not just more graspable by the metaphysician, but also a real ground to differentiate it from other objects.

The assignment was to write a 500-word (no more!) précis of the first chapter of A.E. Taylor’s Elements Of Metaphysics. Being a somewhat long-winded gentleman, I found this to be challenging.

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Metaphysics is a difficult discipline. Its subject matter touches very general and simple issues, impinging on all our intellectual pursuits, yet benefiting from nothing like a well-established consensus or authoritative laboratory experiments.

Some deny the possibility or propriety of metaphysics. All such denials are self-contradictory, always making metaphysical claims in the process of denying that such claims can be made. Further, if one would hold the problems of metaphysics to be intractable, one would be committed forever to the disheartening inseparability of appearance from reality.

Metaphysics attempts to rescue appearances from the scourge of contradiction, replacing troublesome cases with a coherent and non-contradictory view of reality. When we think validly (or “logically”), we attempt to think about what is true or real; hence the law of non-contradiction is no mere logical law, but a fundamental metaphysical principle as well.

Metaphysics thus separates reality from our experience of it, but it is the latter which still forms the discipline’s raw material. Taylor describes experience as “immediate psychical fact” (p. 23). It is concerned with the direct perception of real objects, or objects which can actually have some direct connection “the psychical life of a sentient subject” (p. 24). Thus “real” objects are those which actually have this connection or would have it if all conditions of perception (except the presence of the perceiver) were actually to obtain.

Reality cannot be a succession of states of consciousness, since a state of consciousness requires a subject to be having it, which subject would not itself a be state of consciousness. Similarly, contra Hume, reality cannot be a “series of impressions and ideas connected by psychological laws of succession,” (p. 29), as these facts and laws would constitute part of reality, but would not themselves be impressions or ideas.

Experience is immediate, being incorrigibly distinct in the moment from the memory of an experience or later reflection on past experience. Experience is composite, having both the fact of its immediate existence (the that) and the content of the experience itself (the what). Only the perfect, or “pure” experience of all things and all their implications in one perfect experiential instant would fully suffice us our metaphysical purposes, but this kind of experience is inaccessible to us. Hence to best inform our fallible metaphysical investigations, we must identify the characteristics of this “pure” experience and understand how our actual experience differs from it.

Metaphysical method must be analytical, analyzing experience with an eye toward discovering its broader implications. It must be critical, seeking to criticize previous thoughts in light of current discoveries. It must be non-empirical, refusing to accept facts or observations without analysis. Finally, it must be non-inductive, being independent of confirmation from outside our data.

Taylor’s description of the discipline of metaphysics is helpful, and his rebuttal of the denials of metaphysics is outstanding. His description of “real” objects seems trustworthy, but is not entirely satisfactory. Without having any flaws obvious to this reader, it seems vulnerable to attack by the astute critic.

As promised, here is my first paper for PR-501. It is my answer to the following question:

How does the general postmodernist approach to truth challenge the task of Christian apologetics in the contemporary world? Your answer should include the following four areas:

1. The nature, purpose, and justification of Christian apologetics. Give biblical support.
2. The importance of worldview for apologetics.
3. What the Christian worldview is.
4. A basic strategy for defending the Christian worldview (apologetic method) in the postmodern context.

If it strikes you as breathlessly terse at points, you’re on to something. You’ll also notice that it doesn’t so much end as it does run up against some invisible barrier: in this case the last line of the seventh page of double-spaced 12-point text with 1.25″ margins. I make many assertions that I would normally never leave unjustified in a blog post, but to do them justice might double the size of the essay, and that was just not allowed. (In all fairness, professors and their graders can only read so much text, and there are close to 100 people in the class. Length limitations are only humane.)

Finally, the preponderance of Doug Groothuis citations can be explained easily by noting that he’s the teacher of the class–and a very fine one at that.

Enough caveats. This is pretty much exactly what I turned in four hours ago, just HTML’d up a bit. Read and comment:

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It is the new received wisdom that we are experiencing a radical transition between intellectual eras. The old primacy of rationality, method, and word is passing away, replaced by an emerging world of community, radical pluralism, and image. We are told that the old apologetic paradigms that focused on winning arguments and proving absolute truth claims are relics of an oppressive, Modernist past to be cast off as we reshape the ancient Faith into terms set by atheistic philosophers in recent decades. Is this dramatic paradigm shift warranted? Do traditional apologetic fail to meet the challenges of the postmodern world?

A thorough interaction with all of the claims of postmodernist Christianity is beyond our present scope. Instead, this paper will examine the challenge posed to traditional Christian apologetic methods by the postmodern intellectual milieu, and will propose a strategy for apologetic interaction with the present generation of men and women in Western culture. The new intellectual consensus requires not a radical recasting of Christianity, but instead suggests several minor, evolutionary changes in the practice of apologetics. These changes consist primarily in a more thoughtful approach to postmodernity’s endemic pluralism, better preparation to defend the classical Christian view of truth, and a renewed emphasis on the Biblical priority of the relational context for apologetics and evangelism.

The Nature, Purpose, and Justification of Christian Apologetics
To pursue this improved strategy, we must understand thoroughly the nature and purpose of the enterprise of Christian apologetics. Doug Groothuis defines apologetics as “The rational defense of the Christian worldview as objectively true and existentially engaging.” Apologetics so construed is undertaken in order to bring glory to God, to reach the lost, to encourage doubting believers, and to aid in the sanctification of believers who seek to deepen their knowledge of God.¹We find ample Biblical justification for this endeavor. The classical proof texts in support of the antithetical defense of Christian claims are Peter’s command that believers should “�always [be] prepared to make a defense to anyone who asks you for a reason for the hope that is in you”² and Jude’s injunction to “�contend for the faith that was once for all delivered to the saints”³ against false teachers in the church. Further, we find apostolic warrant in Paul’s overt apologetic interaction with the Stoic and Epicurean philosophers in the Aeropagus of Athens.⁴ Most persuasively we see a consistent pattern of rational argumentation in the interaction of Jesus with Jewish intellectual leaders and others to whom he ministered. Jesus very deftly escaped the horns of potentially life-threatening dilemmas (Mt 22:15-22), used a fortiori arguments in defense of his teaching on the Sabbath (Jn 7:21-24, Lk 13:10-17), appealed to evidence in defense of his uniquely messianic ministry (Mt 11:4-6), and used reductio ad absurdum arguments for a variety of purposes (Mt 22:41-46, Mt 12:25-27).⁵ Even a cursory survey of the Biblical witness gives the contemporary apologist substantial comfort with the tools of rational discourse when engaging hostile skeptics, false teachers, and seeking souls in the defense of God’s truth.

Against recent claims that postmodern people have moved beyond the “white male myth” of logic and propositional truth, we may observe that logic is tellingly employed even in the defense of these claims. As bearers of the imago dei, all human beings have the capacity and indeed the need for rational thought. We may be irrational and inconsistent at times, and sin may cripple the use of our rational faculties even unto our own deaths, but the basic capacity to work out our thoughts in a non-contradictory framework remains as an unchanging part of our nature. Changes in the intellectual climate, be they real or imagined, are powerless to alter this fact.

The Importance of Worldview for Apologetics
A hypothetical apologist in sixteenth-century France might have had to engage his interlocutors on matters of ecclesiastical authority, the doctrine of justification, what systems of civil government are most consonant with Biblical principles, or in the case of extraordinary cross-cultural outreach, possibly a discussion of the uniquely messianic role of Christ with a Jewish neighbor. Even in the latter case, he might never–given a long life of fruitful ministry–encounter anyone with a basic framework for understanding life that differed materially from his own. This state of affairs no longer obtains for any nontrivial case in the postmodern world.Because postmodernity is fundamentally pluralistic, the contemporary apologist must have a robust understanding of the concept of worldview and its effect on human thought. Sire defines a worldview as follows:

A worldview is a commitment, a fundamental orientation of the heart, that can be expressed as a story or in a set of presuppositions (assumptions which may be true, partially true, or entirely false) which we hold (consciously or subconsciously, consistently or inconsistently) about the basic constitution of reality, and that provides the foundation on which we live and move and have our being.⁶

More succinctly, a worldview is a collection of “words and concepts that work together to provide a more or less coherent frame of reference for all thought and action.”⁷ Every human soul of even nominal mental acuity is in possession of a worldview, be it true or false or consciously defended or passively breathed in without any examination at all. This worldview forms the semi-permeable membrane though which all words and concepts must try to pass before they are taken into the mind, finally arriving intact, significantly modified, or not arriving at all. It is antecedently obvious that effective apologetic interaction depends sensitively of the characteristics of this membrane, both as it occurs in the mind of the apologist and in the mind of skeptic, doubter, or false teacher.

Sire proposes that a worldview can be defined by its answers to the following seven questions (the proposed answers are illustrative, not exhaustive):

1. What is ultimate reality? God or the material universe?
2. What is the nature of external reality? Ordered or chaotic? Existing objectively or only as it is perceived by subjects?
3. What is a human being? A molecular machine or God’s image bearer?
4. What happens to a person at death? Annihilation, reincarnation, resurrection?
5. Why is it possible to know anything at all? Because the same Divine Mind that conceived and created the universe also created our minds? Or is knowledge actually not possible?
6. How do we know what is right and wrong? By relative levels of pleasure and pain, by evolved survival mechanisms, or by revelation from God?
7. What is the meaning of human history? To perfect human society? To please God? Or is it meaningless? ⁸

Any given worldview-holder may be able to produce sophisticated, consistent, and defensible answers to all of these questions, or she may not be able to answer any of them in objective terms. However, she has and believes answers to all seven questions, even if she resorts to skepticism or agnosticism on any point. These answers will have a profound impact on how she receives the truth claims of Christianity (or any other sensory or conceptual input), so they and their relationship to the Christian worldview must be understood well by the apologist seeking effective communication and authentic interaction.

The Christian Worldview
Sire’s proposed worldview model can be applied effectively to Christianity. Indeed, if the aspiring apologist lacks the resources to study any other worldview–which privation would itself pose a severe handicap–knowledge of the Christian one is certainly a necessary condition of meaningful apologetic interaction. Starting from Sire’s answers to the questions of Christian worldview, we might propose the following:

1. Ultimate reality is the triune, transcendent, immanent, omniscient, omnibenevolent, sovereign God.
2. External reality exists objectively and is ordered, having been created ex nihilo to operate “with a uniformity of cause and effect in an open system.”
3. Human beings are volitional creatures created in the image and likeness of God, and therefore bear dignity and purpose that is otherwise alien to their nature.
4. Upon death, human beings face a single resurrection to a physical body which then experiences an eternal state of felicity with God or eternal torment.
5. We can know about the external world because the Mind that created it also created our minds in his image and likeness. In addition to this ability to discover the world accurately, God reveals knowledge to us using language.
6. Ethics finds its source in the character of a good God. What is right and what is wrong flow from his immutable nature; and these categories are knowable through conscience and revelation.
7. “Human history is a linear, meaningful sequence of events leading to the fulfillment of God’s purposes for humanity.”⁹

Speaking more succinctly, a Christian might describe the world as created ex nihilo by God, populated by God’s fallen image bearers who can be reconciled to their creator through the cross of Christ, and headed toward a point of historical consummation in which God’s utterly good purposes for his creation will be fully realized. Even this skeletal understanding can begin to provide a meaningful framework from which to engage postmodern men and women thoughtfully and sensitively.

A Postmodern Apologetic Strategy
Notwithstanding the urgency of recent calls for a radical reassessment of Christianity in light of the putative needs of postmodern people, human beings do not change much over time. Intellectual climates and prevailing attitudes change in readily observable ways, but the questions that rob men and women of sleep in the middle of the night are few and well-known. Likewise the immutable laws of consistent thought cannot change any more than we can begin thinking with our kidneys. Apologists can take heart that their subjects are still people, and people still reason the same way about essentially the same questions they did 2,000 years ago.Human society, in contrast, is evolving ever more rapidly. We must also be careful to discern how our generation’s seemingly fluid zeitgeist influences the thinking of those to whom we minister apologetically. The postmodern apologist is guaranteed to encounter a wide array of significantly divergent worldviews, totally unlike her hypothetical French counterpart of the High Middle Ages. This requires her to think in terms of worldview and to have a working knowledge of the worldviews she is most likely to encounter in her ministry.

The contemporary apologist should also expect to find fundamental disagreement on the nature of truth itself. Whereas the Bible views truth as revealed, objective, absolute, universal, engaging, specific, antithetical, and systematic,¹⁰ the typical postmodern is more likely to see truth as constructed, subjective, relative, trendy, and fragmented. While preparation in comparative worldviews may be the first educational task to be mastered by the apologist, agreeing on the nature of truth–and vigorously defending the Biblical view thereof–is surely the primary logical task in any given apologetic engagement. Without consensus on the Biblical view of truth, meaningful discussion and possibly even knowledge itself are ruled out.

Given a new sensitivity to the diverse worldviews likely to be encountered today and a readiness to defend an intellectually functional understanding of truth, the postmodern apologist is finally advised to engage in apologetics relationally. Postmodern men and women know what it is to be the target of a mass-market ad campaign, and they understand viscerally the utter insincerity and lack of personal concern entailed in such an appeal. To communicate to them unintentionally that they are the subject of some rote method or the target of a large-scale crusade in which they yet again a tiny part of the denominator of some impressive statistic is to ensure that our defense of Christianity will be rejected. Engaging them as persons, soul-to-soul, with authentic concern for the existential import of their questions, is a more Biblically faithful way to earn their hearing.

With these tools in hand, the apologist to the postmodern world can continue to approach unbelievers and doubters with confidence.

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¹Douglas Groothuis, Defending The Christian Faith class notes, Denver Seminary, 31 August 2004.
² 1 Pet 3:15 (ESV)
³ Jude 3 (ESV)
⁴ Acts 17:16-33
⁵ Douglas Groothuis, On Jesus, Wadsworth Philosophers Series, (United States of America: Wadsworth, 2003), 26-35.
⁶James W. Sire, The Universe Next Door: A Basic Worldview Catalog, 4th ed. (Downers Grove, IL: InterVarsity Press, 2004), 17.
⁷Ibid.
⁸Ibid, 20.
⁹Ibid, 26-44.
¹⁰Douglas Groothuis, Truth Decay, (Downers Grove, IL: InterVarsity Press, 2000), 65-79.