(Turning to the others.)
Can we clear a little ground first? This programme, as you heard, is called “From World to God?,” so I take it that some forms of natural theology, those which do not begin from the world, are not going to be included in it.
geoffrey
Yes, that’s right. There have been attempts, for example, to prove the existence of a God from purely abstract considerations—the “ontological arguments”—or from the existence of right and wrong. I shouldn’t mind taking Leslie up on such matters one day, but not here and now. They aren’t really arguments from the existence or nature of the world.
leslie
Though perhaps our sense of right and wrong might be regarded as a feature of the world, part of its nature? So might the existence of alleged religious experiences. But yes, the idea is to confine ourselves in these dialogues to the world apart from inner human experiences. Not of course apart from human experience altogether; without that we shouldn’t know there was a world at all!
myra
Kant maintained that there were only two ways one could even try to argue from the world to God: you could start from the detailed constitution of the world, or you could start from “indeterminate experience,” that is, from the existence of anything at all. “More than that there are not, and more there cannot be.” Perhaps we could use this as a starting-point?
geoffrey
That’s all right by me. I might add that Kant himself rejected both of them.
leslie
I think he rather oversimplified the situation, mind you.
myra
How do you mean, “oversimplified”?
leslie
Neither is one straightforward argument: rather, each is a group of more or less similar or related arguments. If you start from “the detailed constitution of the world,” what features of it are you interested in? And if you start from “the existence of anything at all,” well, is there really only one way in which theists have tried to get from that to a God? And some in each group are a lot stronger than others.
myra
Well, then, suppose you explain how one of them might be broken down into these groups of yours. I suggest trying the more general one first.
The “Cosmological Argument”
leslie
Very well. This is what Kant called the “cosmological argument”—or group of arguments, I’d say myself. I should say it could be divided into three sub-groups; and in each of these you will find different people giving different versions.
Firstly, there are those which argue that the universe must have had a beginning in time, and that this first event must have had a cause or reason for it; and the only reasonable candidate for this is the creative will of God. This argument was used extensively in the earlier part of the Middle Ages, by Jewish, Muslim and Christian thinkers alike. They felt that it suited well with what they believed anyway about the beginning of things. God, they knew, had in fact created the world at some point in the past; and surely it must be possible to show that He had.
Secondly, there are those which argue that, irrespective of whether time had a beginning, you need a start to the chain of cause and effect that we observe around us, a First Cause—which we call God. This was the dominant form in the later Middle Ages, though it goes back to earlier times, to the fifth-century “Neoplatonist” philosopher Proclus. A variation of this argues that everything in the created world is a “contingent” being, that is to say, one which might or might not have existed, and that the existence of these implies that of a “necessary being” who couldn’t not-have-existed. (This is the form Kant had chiefly in mind.)
And thirdly (it might perhaps be considered yet another form of the second, but I’d prefer to keep them distinct), you have arguments which seek to show that there has to be an explanation for the universe considered as a whole, as a unity. Causes within the universe can explain effects within it: they cannot explain the whole system of which they themselves are a part.
The Beginning of the Universe?
myra
I hope we don’t need to go into the details of arguments from the early Middle Ages. Couldn’t we be more modern? After all, hasn’t your first sub-group enjoyed a new lease of life in recent days, with the development of so-called “Big Bang” theories of the universe, which seem to show that there really was a beginning of it all, something like 15,000 million years ago? What do you say, Geoffrey?
geoffrey
If this sort of theistic argument is to get off the ground, it needs to show, firstly, that the universe did indeed have a beginning in time, and secondly, that if it I did, this requires a God to explain it. I should query both of these assertions.
myra
A theory was popular at one time called the “steady-state” theory of the universe. The idea was that the universe would look very much the same at any time in its history, and that this history had no beginning. Now none of us is a scientist; we have to take these matters on trust from the people who are; but they seem almost all agreed that there really was a “big bang,” and that the steady-state view did not fit the facts.
geoffrey
Oh, no, that wasn’t what I meant. (Though of course scientific theories do change; you never know what may come next.) Like many other atheists and agnostics, I quite accept that there probably was a “big bang.” But does this necessarily entail a beginning? I had in mind two possibilities. One is the possibility that the universe ends in a “big crunch.” At the time of the “big bang,” the matter of the universe was all compressed together; then it expanded outwards; but in due course it will reach a maximum and begin to contract. Eventually it returns to something like its pre-expansion state—and then it expands again. And of course before our “bang” there was an earlier contraction, and so on. That way you get the “bang” but no beginning of all things. There is an endless cycle.
myra
But isn’t there an objection to that, that as you work back, each expansion would be smaller than its successor? In that case, you would eventually come to an “expansion” which was infinitely small—in other words, to a beginning.
geoffrey
Not if each expansion were (say) half the size of its successor. That way, as you worked back, each oscillation would be smaller than its successor, but there would be no beginning. If our oscillation reached a size of x light-years, the previous one would have reached x/2 light-years, the one before x/4, and so on. However far back you went, there would be no “infinitely small” oscillation.
leslie
But wouldn’t each cycle also be shorter than its successor? Moreover, radiation from each cycle would accumulate, and by now there would be huge amounts of it in the universe—maybe an infinite amount. There isn’t. Nor is there the high or infinite degree of entropy (roughly, disorder) that there ought to be after so many oscillations.
geoffrey
That may be. But in any case it seems that you might have a “crunch” in which the whole system of laws of nature was dissolved and took shape again in (quite possibly) some totally different form; and in that case you couldn’t conclude that the cycles would die down.
leslie
But could you talk of a “cycle” at all in such a case? If the new universe has nothing at all in common with the previous one—matter has been crunched into a state where its former laws no longer apply—I don’t see what meaning there can be in saying that it’s the same universe bouncing back. It would be simpler just to say that there are other universes besides this one, and keep the beginning of time. And if the laws change so much, how can we be sure that