I started reading a book last night on First Cause and intelligent design arguments for the existence of God. These are intellectually fun to read because the author is usually bringing up an argument about science or logic, and I like those things. This latest book is “Who Designed the Designer”, by Michael Augros. Augros is a philosopher working within the Thomistic tradition (Aristotle and St Thomas Aquinas). The book itself preps you for expecting no scientific argument, but lots of common sense argument.
Now I promise, I’m not going to write a blog about every page of the book, because I’m sure it doesn’t really deserve that level of scrutiny, and I wanted this blog and site to be about writing. But here is one analogy that crosses over enough to SF that I’ll give some space.
Augros asks the reader to consider a lamp hanging from a chain. One end of the chain is attached to the lamp, and the other to a beam. For the purpose of hanging the lamp, he says, there has to be a first link in the chain that is attached to something that is ‘not hanging’. If you added links and raised the beam, you haven’t changed anything. Adding “an infinity of links” wouldn’t change anything. There has to be a first link.
No, not really. This is what happens when you try to write logical philosophy using common sense terms and loosely agreed upon understandings of the world.
Since the example is about hanging, and hanging is a result of gravity, you have to examine the unusual cases that most people (like philosophers) don’t think about but scientists and science fiction writers do. In SF there is a very well known idea of the skyhook, or space elevator, which really is a chain or cable hanging from nothing at all. The concept forms the basis of Arthur C. Clarke’s novel, Fountains of Paradise.
The science, briefly, is that you can have an object in orbit around the Earth such that the orbit is as long as a day. This means the the object stays in one place over the surface of the Earth, what we call a geosynchronous orbit. These orbits are used today for communications satellites, an idea Clarke thought of in 1947.
From such a satellite let out two cables, one down toward the Earth and the other outwards. The two cables balance each other so that the overall center of gravity stays in the geosynchronous orbit. Tidal forces will cause the two cables to stretch out and align themselves along a line pointing towards the center of the Earth.
A cable like this can be hung down from space, through the atmosphere, all the way to the ground as the other end reaches farther and farther out into space. From the end just above the ground, you can hang a lamp. Ta-dah, a cable hanging from nothing!
That is the problem with appealing to common sense notions when talking about very abstract ideas. You can’t appeal to the reader’s physical intuition, because that intuition is flawed.
(Of course, you can pursue the hanging analogy if you want. You can say that the cable is hanging from itself, or from the satellite.)
What about the idea of an infinite chain? Well, since we’re talking about gravity, an infinite length of chain is going to be infinitely heavy. It will not only resist the pull of the Earth on the lamp; it will pull the lamp and the Earth into a black hole. Again, the curse of appealing to physical intuition.
Putting aside the physical reality for a moment, is it even sound reasoning to pass from an argument based on a finite number of link to an infinite number of links by just saying “an infinity of links”? No, infinity is not a number that is just a little bit bigger than any number you can think of. Augros says in his introduction that numbers, six in his example, are very definitely even or odd. Infinty isn’t even or odd, prime or composite. It is a different category entirely, and using phrases such as “an infinity of links” shows that Augros really doesn’t understand that, or is happy to equivocate to advance his apologetic position.
What I’ve tried to show in looking at this one argument is the following. Examples of particular situations always get caught up in the details. Our physical intuitions are actually extremely poor guides, and just because Aristotle framed his argument in terms of ship building and other physical activities does not mean that the analogies are very good. We have no natural intuition of infinity in any sense, and so appealing to our intuition is especially false in this case. Finally, we can start to get a taste of how hard it is to attach logical arguments to the reality of the physical world.