The Teleological argument is based on the findings of cosmologists over the past 40 years, that if a number of laws or universal constants had been a little different, the universe would not support life, and may not even exist at all by now. The scientific facts on which these conclusions are based are outlined in Science and the design of the universe. Here we look at the formal philosophical argument and the objections made to it.
The word ‘universe’ is used in two slightly different ways – it can mean the space-time that we live in, which began at the big bang (I will call this ‘our universe’), or all space-time, matter and energy that has existed, which may be more than our universe (I will call this ‘the universe’ or the ‘multiverse’). It is possible that the universe/multiverse consists of a series of universes leading up to our universe, or many universes existing in parallel; equally it is possible that ‘our universe’ is all there is and it and ‘the universe’ are one and the same. (Note that some of the quotes say “the universe” when, in these terms, they mean “our universe”.)
God, if he exists, is not physical, and would be outside the universe, outside of space and time.
The teleological argument
- The character of our universe is determined or described by physical laws and constants.
- If these laws and constants had been different, life would probably not have arisen.
- The laws and constants which led to this suitability for life must have been determined by either physical necessity, chance or design.
- The laws and constants have not been determined by physical necessity.
- The laws and constants have not been determined by chance.
- Therefore our universe was designed.
Premise 1 is obvious and uncontroversial, but the remaining premises require justification.
Premise 2 is the conclusion of most cosmologists. For example Martin Rees, one of the world’s most respected cosmologists, and John Gribbon write in ‘Cosmic Coincidences’:
If we modify the value of one of the fundamental constants, something invariably goes wrong, leading to a universe that is inhospitable to life as we know it …The conditions in our universe really do seem to be uniquely suitable for life forms like ourselves.
Paul Davies says:
There is now broad agreement among physicists and cosmologists that the universe is in several respects ‘fine-tuned’ for life … [or] rather it is fine-tuned for the building blocks and environments that life requires.
Premise 3 is simply a statement of the possibilities. It is difficult to find any others. The logic is this: Either our universe could have been different or else it couldn’t (physical necessity). If it could have been different, it took this form either because it was designed or not designed (chance).
Premise 4 is the same as saying there is an underlying physical “law” that determines the characteristics of our universe – sometimes called a ‘Theory of Everything’ (ToE). However we can say of a ToE:
- We do not currently have such a theory, and it isn’t certain that we ever will.
- A ToE, as currently conceived, has the purpose of providing a unifed explanation of the four fundamental forces (gravity, electro-magnetism, the weak nuclear force and the strong nuclear force); explaining the universal fine-tuning is way beyond this.
- Many cosmologists say the nature of the fundamental laws and the values of the constants do not seem to allow of such an explanation, and so Martin Rees (in ‘Just Six Numbers’) eliminates underlying physical laws or a ToE from his list of possible explanations of fine-tuning. Currently the most promising possibility for a ToE is string theory, but Stephen Hawking said:
Does string theory predict the state of the universe? The answer is that it does not.In other words, string theory does not provide the physical necessity for the universal fine-tuning.
- Finally, even if the laws could be seen to inevitably lead to a hospitable universe, we are faced with the dilemmas of (i) how these laws could exist in the state of nothingness before the universe commenced, and (ii) how is it that the fundamental reality was like this? It doesn’t seem to make sense.
Thus Paul Davies concludes:
It seems, then, that the physical universe does not have to be the way it is; it could have been otherwise. and Lee Smolin says:
It strains credulity to imagine that mathematical consistency could be the sole reason for the parameters.
Premise 5 is considered to be virtually impossible by almost all cosmologists – the fineness of the tuning is immensely improbable by chance. The following quotes from eminent cosmologists show this:
To make the first 119 decimal places of the vacuum energy zero is most certainly no accident. Leonard Susskind (‘The Cosmic Landscape’)
Perhaps before going further we should ask just how probable is it that a universe created by randomly choosing the parameters will contain stars. Given what we have already said, it is simple to estimate this probability. For those readers who are interested, the arithmetic is in the notes. The answer, in round numbers, comes to about one chance in 10^229. Lee Smolin (‘Life of the Cosmos’)
This now tells us how precise the Creator’s aim must have been: namely to an accuracy of one part in 10^10^123. This is an extraordinary figure. Roger Penrose, former Professor of Mathematics at Oxford University and a cosmologist who worked with Stephen Hawking (‘The Emperor’s New Mind’)
Conclusion (proposition 6): The argument is logically valid and its premises seem more probably true than false. Thus it leads to the probable conclusion that our universe was designed. The argument stops there, but, when combined with other arguments, it is reasonable to conclude that the only possible designer is God.
Not surprisingly, there are many objections to the argument.
Physicist Victor Stenger has constructed a computer model that shows that about half the possible universes would exist long enough to allow stars and planets to form. However the model is very simplistic (it doesn’t account for more than a few of the required parameters) and his conclusions are in direct contradiction with Rees, Davies, Penrose and Smolin, and he doesn’t seem to have convinced any cosmologists and Luke Barnes has shown that Stenger’s model is based on incorrect understandings and wrong equations.
Stenger has also argued that this conclusion is based on the assumption that life must be carbon-based as on earth. But small changes to some of the constants make it unlikely even that stars or planets would form, or that any atoms other than hydrogen or perhaps helium (which are not enough to make anything nearly as complex as life) would form, or even that our universe would last long enough to allow life to form. Again, Stenger doesn’t seem to have convinced many cosmologists of his arguments here.
The most common scientific explanation of the fine-tuning is the multiverse hypothesis – that our universe is part of a much larger universe (often called a multiverse) which has generated a large number of universes. If there were enough of these alternative universes, and if each one had different settings of the laws and constants, then eventually an inhabitable universe would be created and that is the one we find ourselves in. Outlandish as this idea might appear at first, cosmologists believe it is consistent with current cosmological theory, even though other universes could never be observed.
However the multiverse hypothesis doesn’t appear to be sufficent to throw doubt on Premise 3, for the following reasons:
- Some cosmologists reject it as a scientific hypothesis because, it is believed, it can never be observed or verified.
- It requires that the multiverse be capable of generating billions of universes each with a different set of parameters. But, as Paul Davies has pointed out, such a multiverse would have to be fine-tuned to produce such an outcome, which simply brings us back to the same difficulty – is it this way by necessity, chance or design?
So it appears the same three possibilities remain even if the multiverse is considered to be possible.
It remains possible that science will one day find an underlying reason or law which makes the characteristics of our universe inevitable. Despite the fact that we don’t have this now, that some cosmologists doubt we ever will, and that it is hard to see how the ‘nothing’ out of which our universe appeared could have contained any laws, this remains a possibility. Whether it could be considered a probability is more a matter of faith or personal preference than of science. But it is interesting that the current interest of cosmologists in the multiverse throws this objection into serious doubt, because they all assume that each universe within the multiverse has different settings, and so are not fixed by physical necessity at all.
Perhaps the most common objections to the design argument are based on probability. How do we know that all of the possible settings are equally likely? How do we know the settings in our universe are statistically independent? But these and other similar objections lose their weight when we consider the enormity of Roger Penrose’s estimate of overall probalility.
More fundamental is the argument that it is meaningless to talk about probability when we only have one known universe and no frequncy distribution of universe on which to make a judgment of probability. But this objection also seems to founder on the rock of the conclusions of cosmologists.
- There are forms of statistics which can deal with this situation. And if we consider the set of all possible universes, a frequency distribution can be calculated.
- More telling is the fact that Roger Penrose was Professor of Mathematics at Oxford University and clearly qualified to make a judgment on the validity of making statistical estimations of the probability of our present universe occurring by chance. And he is the one who made the probability estimate most often quoted. So in answer to the objection that probability cannot be used, we can say that it has been used.
- Even if a numerical probability estimate could not be made, the cosmologists make descriptive statements that indicate how improbable it is that our universe occurred by chance.
The multiverse doesn’t help with the probability objection either. Currently string theory predicts that, if there is a multiverse, there would be 10^500 universes. This is an enormously large number, but only an infinitessimal fraction of Penrose’s estimate of probability. Even 10^500 universes don’t make our universe even remotely likely by chance.
Conclusion (proposition 6)
There are objections to the form of the conclusion also.
- We shouldn’t be surprised that we live in a universe that supports life, because we wouldn’t be here if it didn’t.
But this objection (sometimes named ‘the anthropic principle’) has been shown to be a logical fallacy. Of course, granted we are here, it must be true that our universe supports life. But how likely is it that we are here (i.e. out of all the possible universes, how many could support life?), and what is the explanation? Which ever way we look at it, the present situation is highly unlikely, and the design argument can legitimately ask for an explanation.
- Who designed the designer?
If the universe requires an expanation, then so does God. We gain nothing by this explanation, it is said. But all scientific explanations have the same form, they explain one thing in terms of something else. If this objection was true, then all scientific explanations would be disallowed also. The truth is that every step backwards in an explanatory chain gains us knowledge. Then why stop at God? But we are not compelled to stop at God – it’s just that we seem unable to go further, and a logical place to stop (and so avoid an infinite regress) is at a necessary being.
- The argument doesn’t prove that God is the designer.
This is true, but arriving at a conclusion that the universe was probably designed is a significant achievement. It is hard to see how anything other than God could have designed the universe, especially when this argument is combined with other arguments, such as the Cosmological.
There also seem to be a collection of erroneous or unjustfied objections to the design argument. For example:
- Perhaps there could be natural selection of universes which are formed by the multiverse.
- Why would God create a universe in this way?
- David Steele states: No attempt has been made to show that the emergence of life is improbable …., when in fact the calculations of Penrose and Smolin do exactly that.
- Steele also argues that the improbable conditions may not be independent, then argues that this changes the probability calculation, which he assumes is done by multiplying the probabilities of separate events. But my understanding is that Penrose didn’t calculate his probability that way, but by looking at the full sample space of possible universes and the number of low entropy universes.
Thus these ‘objections’ tend to strengthen rather than weaken the design argument because they seem rather desperate attempts to find something to disagree with, and hence tacit admittals that the argument is strong.
This seems like a strong argument. It has a common sense feel about it, and the objections do not. The only objection which seems to have any weight at all is the thought that perhaps one day we will find an underlying physical cause. I haven’t found many cosmologists who seem comfortable with this, and it remains true that at the present time we have nothing which could supply such a cause.
The multiverse, which is the favoured scientific explanation, really doesn’t change the argument as formulated here. The probability of it all happening by chance remains vanishingly small, and there is no hypothesis of physical necessity on the horizon.
The designer hypothesis isn’t competing with any scientific hypothesis such as the multiverse. This form of the argument simply requires any scientific hypothesis to be tested against the three possibilities of necessity, chance or design. So far, design seems to be by far the most probable.