Space news

I posted below about NASA's plans to look for water on the Moon, but it's already been discovered; see here and here. So the debate whether to return to the Moon first or just skip it and go straight to Mars (which I've posted on) just got a little more interesting. This apparently ticked Mars off, so it revealed it has water ice to up the ante.

Unrelated but interesting: the Messenger spacecraft (which I've also posted on) is swinging by Mercury for the last time today before it settles into orbit around it in March 2011.

Update (2 Oct): Mercury pictures.

The Meaning of Life

There has been much discussion in the last several years about the possibility of extending the human life span. As futuristic as it sounds, medical research is uncovering possible methods by which the maximum age could increase from about 120 years to 160, 180, 200, and just keep on going. Some argue against extending lives because they believe it to be unnatural. I have no sympathy for this view. I don't see how this objection wouldn't also apply to any and every kind of medical treatment.

That's a post for another day though. For now, I just want to emphasize what the possibility of extending life spans does not do. Avoiding death is a good goal to have, but the mere extension of our lives can never satisfy. Immortality is not enough: we need meaning. We need a meaningful life. The atheist existentialists tried to address this, but never really went beyond the suggestion that we should pretend our lives have meaning even though they really don't. Others may say that making other people happy or making a difference in society would do it. But that doesn't give any real meaning, only a relative meaning. That is, if the happiness of others or the betterment of society has no meaning, then working towards one of them is simply arbitrary. If changing the world for the better is pointless and meaningless, then why bother? Why not work towards making other people suicidal, or for the downfall of civilization instead? If our existence doesn't have any significance, any purpose, any meaning, then what motivation is there to do or say anything?

It seems to me that the only serious answer one could give would be pleasure. But this has several problems:

First, when we pursue pleasure, we tend to become sickened. If we seek pleasure with food and gorge ourselves, or with alcohol and drunkeness, it stops being fun. This doesn't just mean that if you eat or drink too much you'll get sick. It also means that if we regularly gorge ourselves, or regularly get drunk, it tends to become less and less pleasurable.

Second, if someone gets pleasure from something that is harmful to others, like child-abuse, what could motivate them to not pursue such pleasure? Well, the danger of being caught perhaps. But this only means that such a person would only abuse children when he's confident that he can get away with it. A sophisticated murderer would only kill people whose lives have less impact on society, and therefore their deaths would also have less impact; and so he would be able to get away with it. This is simply unacceptable.

Third, seeking pleasure is something everybody does. If it really led to the highest satisfaction one could achieve in life, why would anyone think otherwise? It's like that Calvin and Hobbes comic where Calvin taped paper wings to his arms so he could fly. Hobbes asks him "If paper wings is all it takes to fly, don't you think we'd have heard about it by now?" If pleasure is all there is to life, don't you think everyone would have realized it by now? But we don't: we realize that there is more to life, although we often can't put our finger on it. Peter Kreeft and Ronald Tacelli, two Catholic philosophers from Boston College, wrote that to live solely for pleasure "is the stupidest gamble in the world, for it is the only one that has consistently never paid off ... every batter who has ever approached that plate has struck out. ... After trillions of failures and a one hundred percent failure rate, this is one experiment no one should keep trying." An essay by William Lane Craig, published as chapter 2 of his book Reasonable Faith, discusses this and similar themes; it's called "The Absurdity of Life Without God". Read it at your own risk.

(cross-posted at Quodlibeta)

Good Reads

I've signed up on Good Reads, a kind of MySpace for books. I'm not doing this to socialize, I'm doing it to keep myself accountable on my research for my dissertation by putting it in the public domain. If I know other people can see at any given moment how much reading I've done and am doing (even if no one actually does) it will, I hope, impel me to get more done. I may cross-post book reviews there and here, although some of the books will be fairly obscure, even among other philosophers, so it might not hold much interest for everyone.

Still More Favorite Movie Scenes

Not necessarily scenes from my favorite movies, yada yada yada.

Raising Arizona


The Chronicles of Narnia: The Lion, The Witch and the Wardrobe


Tom-Yum-Goong (The Protector)


The Shawshank Redemption


Being John Malkovich


Shine

Shine - Flight Of The Bumblebee par apple4b

Twilight Zone: The Movie


The Untouchables


Meet the Robinsons

Infinite Amounts

Many cosmological arguments, in trying to show that the universe is contingent, argue that an actual infinite amount of something is metaphysically impossible, and so could not occur in reality. As such, there could not have been an infinite regress of events or an infinite chain of cause and effect. There must be a stopping point where a cause is not an effect of a cause itself, but is pure cause, not contingent on anything else. "And this all men call God."

The impossibility of an actual infinite has been defended in the last few decades by William Lane Craig, in his book The Kalām Cosmological Argument, his general apologetics book Reasonable Faith, and numerous philosophical articles, some of which were republished in Theism, Atheism, and Big Bang Cosmology, a book he co-wrote with atheist philosopher Quentin Smith. Most of this post is just paraphrases of Craig’s writings. In Reasonable Faith, Craig points out that there is a distinction between an actual infinite and a potential infinite.

A potential infinite is a collection that is increasing toward infinity as a limit but never gets there. Such a collection is really indefinite, not infinite. For example, any finite distance can be subdivided into potentially infinitely many parts. You can just keep on dividing parts in half forever, but you will never arrive at an actual ‘infinitieth’ division or come up with an actually infinite number of parts. By contrast, an actual infinite is a collection in which the number of members really is infinite. The collection is not growing toward infinity; it is infinite, it is ‘complete.’

In other words, an infinite amount of defined units is an actual infinite. An “infinitieth” of something is not a defined unit, so this is a potential infinite. An actual infinite is usually signified by aleph-null, but I can’t figure out how to type that in blogger, so I’ll just use ∞ instead, even though it usually represents indefiniteness rather than infinitude.

While actual infinites are used in conceptual mathematics they do not have any corresponding reality.

1. The most famous illustration of this is Hilbert’s Hotel (named after mathematician David Hilbert). Imagine a hotel with two wings that stretch out infinitely in opposite directions and which therefore contain an infinite number of rooms, and imagine that they are all occupied, that is, the hotel is completely full. Somebody shows up and asks for a room. In a finite hotel the proprietor would have to turn him away, but in an infinite hotel the proprietor could just move the person in room 1 to room 2, the person in room 2 to room 3, the person in room 3 to room 4, etc. Now room 1 is open and the person can check in. But the hotel was already full. Each room was occupied. Moreover, the same number of people are in the hotel even though no one has left and there is one more person than before. This is true for any finite number: if a million new people checked in, you could just move the person in room 1 to room 1,000,001, etc.

A friend of mine once suggested that if the hotel is infinite, then there would be no outside for someone to come in from. This is incorrect. We can easily imagine that the hotel extends infinitely in two directions along a street or something. Someone on the other side of the street (perhaps in the infinite restaurant) could then cross the street and check in.

2. But what if an infinite amount of people come to check in? Does the proprietor tell them that the hotel is full and turn them away? No, he just moves the person in room 1 to room 2, the person in room 2 to room 4, the person in room 3 to room 6, etc., moving each person to the room number double their previous number. He thus empties all the odd numbered rooms and the infinite number of new guests can check in. But before they came, each room was occupied. And again, there are the same number of guests as before, even though the proprietor just increased his occupancy by an infinite amount. And he can do this again and again, in fact infinitely many times, and there would never be one more person in the hotel.

3. Another illustration would be a bookcase with an infinite number of books. If you took seven books off the shelf there would be an empty space where they had been. But there’s still an infinite amount of books left, so therefore the bookshelf is still completely full with no empty spaces.

4. Conversely, if you took out all of the books but seven, you would have taken an infinite amount of books off the shelf. However, if you took an infinite amount of books off the shelf, it would be completely empty; but it’s not, there are seven left.

5. Now what if you took out every other book? That would leave a space between each remaining book. Although you took away an infinite number of books, there’s still an infinite number of books remaining, since there’s an infinite amount of odd numbers and an infinite amount of even numbers. The absurdity of this last example can be realized by imagining that you take the first book and push it up against the third book, so there isn’t a space between them any more. Then push these two books up against the fifth, and all of these against the next one, etc. Then there will be an infinite amount of empty space on the bookshelf (from the infinite number of books taken off it), so it’s necessarily empty. But there are still an infinite number of books left on the shelf. As such, it’s necessarily full. But if the bookshelf is full, the first book would be where it’s always been, even though you just moved it. The bookcase is simultaneously completely empty and completely full. When you look at this bookcase, what would you see?

Obviously, Hilbert’s Hotel and a bookcase like this could not exist in reality. Yet, if an actual infinite amount could exist, they could exist as well. Arguments 1-5 can be reduced to the following mathematical equations (where X and Y are actual amounts, that is, any number greater than zero):

1. X + Y ≠ X but ∞ + Y = ∞
2. X + X ≠ X but ∞ + ∞ = ∞
3. X - Y ≠ X but ∞ - Y = ∞
4. X - X = 0 but ∞ - ∞ = Y
5. X - X ≠ X but ∞ - ∞ = ∞

Note also that 4 and 5 contradict each other: infinity minus itself equals both infinity and an actual amount.

A friend of mine once complained about these arguments by saying that when I add to or subtract from infinity I was treating it like an amount, and this is invalid. That is precisely the point: an amount, by definition, can be added to or subtracted from. Since we cannot do this with infinity, there cannot be an actual infinite amount of defined units. These arguments simply demonstrate this. As Craig writes,

There is simply no way to avoid these absurdities once we admit the possibility of the existence of an actual infinite. Students sometimes react to such absurdities as Hilbert’s Hotel by saying that we really don’t understand the nature of infinity and, hence, these absurdities result. But this attitude is simply mistaken. Infinite set theory is a highly developed and well-understood branch of mathematics, so that these absurdities result precisely because we do understand the notion of a collection with an actually infinite number of members.

Some might object that God is often referred to as infinite. Doesn’t this disprove God’s existence since an actual infinite can’t exist? It does not for the following reason: what makes an actual infinite impossible is that it consists of an infinite amount of units or members (like books or hotel rooms). God is not “made up” of any amount of units. In saying that God is infinite, we are saying he is unlimited by anything. Since God does not consist of a bunch of units, the argument against an actual infinite amount of units existing does not apply to him.

Cool

I've mentioned James Hannam's new book God's Philosophers: How the Medieval World Laid the Foundations of Modern Science, a few times on this blog. I just discovered that his PhD dissertation is available online: Teaching Natural Philosophy and Mathematics at Oxford and Cambridge 1500 – 1570. This is really making it difficult to write my own dissertation.

Bombing the Moon

Popular Mechanics has an interesting article about NASA's plans to crash a satellite onto the Moon in order to analyze the cloud of dust it will kick up for water ice. This would be very important for any future manned stations there. It sounds like a good idea ... at least until you read this post at IMAO or this short story by Fredric Brown.

Norman Borlaug, RIP

In 1999, the Atlantic Monthly estimated that Borlaug's efforts combined with those of the many developing-world agriculture-extension agents he trained and the crop-research facilities he founded in poor nations saved the lives of one billion human beings.
...
Borlaug became the target of critics who denounced him because Green Revolution farming requires some pesticide and lots of fertilizer. Trendy environmentalism was catching on, and affluent environmentalists began to say it was "inappropriate" for Africans to have tractors or use modern farming techniques. Borlaug told me a decade ago that most Western environmentalists "have never experienced the physical sensation of hunger. They do their lobbying from comfortable office suites in Washington or Brussels. If they lived just one month amid the misery of the developing world, as I have for 50 years, they'd be crying out for tractors and fertilizer and irrigation canals and be outraged that fashionable elitists in wealthy nations were trying to deny them these things."
...
Often it is said America lacks heroes who can provide constructive examples to the young. Here was such a hero. Yet though streets and buildings are named for Norman Borlaug throughout the developing world, most Americans don't even know his name.

Read the whole thing. This is one reason why I consider myself an environmentalist even though I don't fit into the usual definition. I think Borlaug is much more of a hero than Rachel Carson.

Oh. Wow.

Here's a video of Voyager 2's flyby of Triton, the largest moon orbiting Neptune. Amazing. Remember that for half its orbit Triton is further away from the Sun than Neptune, the outer-most planet of our solar system.

Abortion and Age-reckoning

One of the arguments for abortion is that we don't count someone's age from the date of their conception, or of quickening, or some other point in utero. We count age from their birth. If we really believed human life began at an earlier stage, we would recognize it here and we simply don't. I've never found this argument convincing.

1) We count age from birth because this is the child's introduction to the public world.

2) Birth is a very dramatic phenomenon with immediate objective results and so supplies us with a very obvious point of reference (whereas conception and quickening do not).

3) This argument would mean that a fetus at nine months gestation is not really a human being, and can therefore be killed without repercussions. Very few people would accept this. This is significant since the whole point of this argument is based on an appeal to common perception and belief.

4) Plenty of cultures throughout history have reckoned age according to the approximate time of conception. This has been common in east Asian cultures for example, like China, Korea, Japan, Vietnam, etc.

Atheism and Conspiracy Theories

On this eighth anniversary of the September 11 terrorist attacks there are still plenty of people who would rather believe that it was an enormous conspiracy carried out by the US government or Jews or whatever. Such claims are, of course, completely ridiculous, not to mention deeply offensive. The best one-stop shop debunking them is Screw Loose Change and the best essay doing the same is the one published by Popular Mechanics. Other refutations, more in line with the seriousness these theories deserve, have been done by Cracked and South Park. I place 9/11 conspiracy theories on the same intellectual level as theories that the Moon landings were fake or that the Holocaust didn't really happen.

In a recent debate with Alvin Plantinga, Daniel Dennett claimed that belief in God is also this absurd. I would argue that it actually goes the other way: atheism is, in a sense, a conspiracy theory. I'm not referring here to the ridiculous claim that Jesus never existed. Of course, that is a conspiracy theory, but I'm thinking of the more basic claim of atheism: that God does not exist, that there is no supernatural, that the natural world is all that exists.

I say atheism is a conspiracy theory in a sense because there are important senses in which it is not. Thinking that all the theistic arguments fail or that the problems of theism outweigh those of atheism does not make one a conspiracy theorist. God's existence is not blindingly obvious, so to compare those who disbelieve in Him to those who think there is a secret cabal of evil Jews running the world is, in many ways, inappropriate. So I don't mean to imply that atheism is on a par with conspiracy theories in general; only when looked at in a particular way.

The sense in which atheism is a conspiracy theory is with regards to religious experience. Throughout human history people have had experiences of "something" beyond the physical world. In fact, this is one of the most common experiences that human beings have. The atheist thesis would require us to believe that virtually all of these experiences are completely illusory. I find this about as plausible as claiming that our experiences of the physical world are illusory. Of course there are differences: everyone experiences the physical world while not everyone has religious experiences; the physical world imposes itself on us constantly, while religious experiences are usually temporary; etc. Nevertheless, the sense of the supernatural, of a "beyond," can impose itself upon us to a much greater degree than the physical world.

Some might object that atheists are not positing any actual conspirators, so to call it a conspiracy theory is misleading. However 1) atheists claim our experiences of the supernatural are simply by-products of how our brains evolved. Evolution is responsible for our having these experiences and thinking they're veracious when they're actually not. So evolution is functioning, at least metaphorically, as a conspirator, even though it lacks something that most other conspiracy theories lack -- mindful intent. 2) My focus is not on the cause of the conspiracy theory but on the effect. Atheists, by claiming that religious experiences are a widespread illusion, are making the same claim as other conspiracy theories: 9/11 wasn't what it seemed to be; the Moon landings weren't what they seemed to be, President Kennedy's assassination wasn't what it seemed to be, etc. Of course, many things aren't what they seem, but to simply dismiss the experiences of billions of people as illusory seems no more reasonable than to dismiss all the eyewitness reports that the Pentagon was struck by a large airplane and assert it was a guided missile instead.

Another possible objection is that religious experiences are radically divergent and contradictory, and this should make us skeptical of their veracity. I would argue that 1) the disagreements have been exaggerated. There are, of course, differing aspects of them and even contradictions, but there is also much more agreement than atheists are often willing to admit. 2) The fact that everyone tells the same story (that there is something beyond the physical world) is more significant than the disagreement of the details. It's therefore strange to claim that the answer must lie in precisely the opposite direction. When eyewitnesses give contradictory accounts of a car accident, we are not justified in believing that no car accident took place. 3) So at most the differences between these experiences would justify skepticism toward a particular account, but not to the phenomenon as a whole. 4) Again, this objection would apply equally to our experiences of the physical world. There are accounts of physical phenomena that neither I nor anyone I know has personally experienced. Such accounts can even seem to contradict the phenomena I have experienced. It would not be rational for me to conclude that all accounts of the physical world are therefore bogus, and all the experiences of it illusory.

Because I can, I'll end with a quote by C. S. Lewis.

If you are an atheist you do have to believe that the main point in all the religions of the whole world is simply one huge mistake. If you are a Christian you are free to think that all these religions, even the queerest ones, contain at least some hint of the truth. When I was an atheist I had to try to persuade myself that most of the human race have always been wrong about the question that mattered to them most; when I became a Christian I was able to take a more liberal view.

(cross-posted at Quodlibeta)

Nagel on Evolution

Thomas Nagel is one of my favorite philosophers. He's been famous in philosophy circles since he published his essay "What Is It Like to Be a Bat?" in 1974. He recently wrote an essay in the journal Philosophy and Public Affairs entitled "Public Education and Intelligent Design". In it he argues (among other things) that evolutionary biologists are over-confident when they compare the certainty of evolution with that of a spherical earth. Nagel thinks this is "a vast underestimation of how much we do not know, and how much about the evolutionary process remains speculative and sketchy." I find this interesting because in The View from Nowhere he argued that proponents of evolution are over-reaching in their application of it.

Evolutionary hand waving is an example of the tendency to take a theory which has been successful in one domain and apply it to anything else you can't understand -- not even to apply it, but vaguely to imagine such an application. It is also an example of the pervasive and reductive naturalism of our culture. 'Survival value' is now invoked to account for everything from ethics to language.
...
Even if randomness is a factor in determining which mutation will appear when (and the extent of the randomness is apparently in dispute), the range of genetic possibilities is not itself a random occurrence but a necessary consequence of the natural order. The possibility of minds capable of forming progressively more objective conceptions of reality is not something the theory of natural selection can attempt to explain, since it doesn't explain possibilities at all, but only selection among them.

This sounds very similar to the Argument from Reason, that some of the properties of mind are inconsistent with naturalism. Victor Reppert has referred to Nagel a few times at Dangerous Idea 2.

Yet while Nagel appears to be anti-naturalist, he is also an atheist. In The Last Word he writes:

In speaking of the fear of religion, I don't mean to refer to the entirely reasonable hostility toward certain established religions and religious institutions, in virtue of their objectionable moral doctrines, social policies, and political influence. Nor am I referring to the association of many religious beliefs with superstition and the acceptance of evident empirical falsehoods. I am talking about something much deeper -- namely, the fear of religion itself. I speak from experience, being strongly subject to this fear myself: I want atheism to be true and am made uneasy by the fact that some of the most intelligent and well-informed people I know are religious believers. It isn't just that I don't believe in God and, naturally, hope that I'm right in my belief. It's that I hope there is not a God! I don't want there to be a God; I don't want the universe to be like that. ...My guess is that this cosmic authority problem is not a rare condition and that it is responsible for much of the scientism and reductionism of our time.

A critique of Nagel's recent essay is at Pure Pedantry. The main point of contention is that Nagel is unaware that science is intrinsically naturalistic. The comments over there are interesting as a lot of them seem to disagree with this pronouncement. Via Keith Burgess-Jackson, another atheist who sides with Nagel.

(cross-posted at Quodlibeta)

Prayer Books

I've written about Dallas Willard before. He's a philosopher who has written some absolutely amazing books on spirituality and Christian living. If you're a Christian I can't recommend his writings highly enough.

His website used to have a page describing his current writing projects and encouraging people to pray for them. Unfortunately, they took that page down a few years ago, although I suppose they had their reasons. But I still remember a couple of the philosophy books he was writing, and desperately want to read them, so I'm very anxious that he continue writing them. It's kind of sad that I still remember the titles, but here they are (at least approximately):

The Disappearance of Moral Knowledge from Plato to Rawls.

Rage Against Identity: The Philosophical and Psychological Roots of Deconstructionism.

I'm going to keep praying for these books. They're not merely philosophy, they also address important social issues which Christians should be educated about.

Gay Marriage and Infertility

An objection often made to gay marriage is that such a marriage could not produce any children. The counter-response is that this would mean that heterosexual couples who are infertile or who simply do not want to have children should also be excluded from marriage. I addressed this claim in this post, but Keith Burgess-Jackson has a much simpler and shorter refutation.

I wrote the other day that "marriage is about children." It might be objected that if this were the case, then childless or infertile heterosexual couples would not be allowed to marry. Here is the objection:

1. If marriage were about children, then neither infertile nor fertile-but-childless heterosexual couples would be allowed to marry.

2. Infertile and fertile-but-childless heterosexual couples are allowed to marry.

Therefore,

3. Marriage is not about children.

This argument is valid, but the first premise is false, which makes the argument unsound. Compare the following argument, which has the same form as the first:

1a. If drinking alcohol were about maturity, then immature individuals who are at or above the legal drinking age would not be allowed to drink alcohol.

2a. Immature individuals who are at or above the legal drinking age are allowed to drink alcohol.

Therefore,

3a. Drinking alcohol is not about maturity.

The first premise of this second argument is false, as even proponents of homosexual "marriage" will concede. There are many reasons of a practical nature, and some of a moral nature, for not disallowing the immature to drink. The drinking age is a bright-line rule that obviates the need for agents of the state to inquire into maturity. Perhaps in an ideal world the law would say that all and only mature individuals may drink alcohol, but our world is far from ideal.

Read the whole thing.

More links

I've added David Thompson's blog, Culture, Ideas and Comic Books, to my blogroll. I recommend checking out his greatest hits. He has a lot of interesting posts on education, post-modernism, and political correctness.

I've added several links to the Web Resources. Google Scholar is, as you could guess, a google search for books in the public domain or for purchase. I haven't used it much, but it seems pretty good. The Internet Archive has just about everything in the public domain or links to them, and Project Gutenberg is pretty much the same thing. Both are excellent.

Two of the new links aren't resources in the same way as the others, since they aren't simply texts available to read or download. However, I'm including them because they give easy access to such resources. The first is AbeBooks, which is essentially a collection of just about every bookstore in the world. I've used it many, many times. Second is WorldCat, which is the same thing for libraries. Thus, you can find out where the nearest library is that has a book you want and get it via interlibrary loan.

Update (9 Sep 2009): Oops, I forgot to include Just Thomism on my blogroll. Done and done.

Cool

A picture of a pentacene molecule:


Each hexagon corner is a carbon atom, and each line away from the main body ends in a hydrogen atom.