In Chapter 8 of The Existence of God, 2nd edition (hereafter: EOG), Richard Swinburne defends two teleological arguments for the existence of God.
The first one he calls the Teleological Argument from Temporal Order (TATO). The factual premise of TATO is that a universe governed by simple natural laws exists. The second argument he calls the Teleological Argument from Spatial Order (TASO). The factual premise of TASO is that a universe (governed by simple natural laws) having natural laws and boundary conditions such that human bodies were likely to have been brought about (by natural processes) exists.
In this post I am going to focus on the second teleological argument: TASO.
It seems to me that there is an obvious and serious problem with TASO:
If God exists, then God probably would NOT have used evolution to bring about human bodies.
I’m getting ahead of myself. First, let me present TASO:
1. The laws and boundary conditions of the universe are such as to make probable the evolution of human bodies.
2. God exists.
This is not supposed to be a proof of the existence of God, but rather (1) is supposed to provide relevant evidence which increases the probability of (2) to some significant degree, relative to the probability of (2) if our only relevant evidence were that there was a complex physical universe that was governed by simple natural laws.
In discussing TATO, Swinburne argues that the existence of a complex physical universe that is governed by simple natural laws provides some evidence for God (i.e. TATO is a good inductive argument), and so the idea is that TASO further increases the probability of God’s existence beyond the degree of probability already provided by TATO.
Swinburne argues for the inductive correctness of TASO this way:
3. It is quite likely that, if there is a God, the laws and boundary conditions of the universe are such as to make probable the evolution of human bodies.
4. It is very improbable that, if it is not the case that there is a God, the laws and boundary conditions of the universe are such as to make probable the evolution of human bodies.
5. The existence of a universe with laws and boundary conditions such as to make probable the evolution of human bodies would provide significant inductive evidence for the existence of God (i.e. TASO is a correct inductive argument).
Swinburne has something very specific in mind when he speaks of ‘human bodies’ in this argument: a body having “features that the body of a humanly free agent, as defined in Chapter 6, would need to have.” (EOG, p.168) He mentions that a body of a humanly free agent “needs to be suited for the acquisition of true beliefs about the environment, the formation of purposes in the light of desires, and the expression of them via chosen basic actions designed to affect the agent, others, and the world for good or ill.” (EOG, p.168-169). Swinburne then outlines seven specific features that a body must have in order to achieve those ends (EOG, p.169).
Premise (4) is argued on the basis of Swinburne’s version of the Fine Tuning Argument (FTA). So, objections to FTA will generally apply to his case for (4).
Premise (3) appears to me to have an obvious and serious problem. A key assumption behind most of Swinburne’s arguments for God is that it is somewhat probable (about .5) that God would choose to bring about the existence of embodied humanly free agents. But it does not follow that God would choose to do so by means of the natural process of evolution. Swinburne realizes that God (if he exists) would have other options:
God could achieve this [bringing about embodied humanly free agents] either by creating such bodies entire, or by creating and keeping in existence a universe designed to bring them about by a long evolutionary process, or even a multiverse designed to bring about such a universe. (EOG, p.188)
So why would God use a “long evolutionary process” to bring about embodied humanly free agents, when God could simply create millions of such beings from nothing in an instant? Why would God, a perfectly morally good person, choose instead to allow evolution to stumble along for a billion years, while trillions of living things struggled and starved and suffered and died painful violent deaths in order to bring about embodied humanly free agents? Such a choice suggests that the creator was a moral monster who has no empathy for the pain and fear and suffering of animals.
What does Swinburne have to say in support of choosing the “long evolutionary process” over the magic of creation ex nihilo? Not much:
If his only aim in creating a universe was to populate it with human beings, there would indeed be no point in producing them by a long evolutionary process. But there are other good features of the universe that God has good reason to bring about. I have commented already on the beauty of the inanimate universe shown in the development of galaxies, stars, and planets. God has every reason for bringing about this process of development from the Big Bang for its beauty… (EOG, p.188)
Am I missing something here? This comment seems completely irrelevant to the question at issue. Let’s grant for the sake of argument that God had good reason to bring about the “galaxies, stars, and planets” by means of a “long evolutionary process”. Nothing follows about God having good reason to use a “long evolutionary process” to bring about either animals or embodied humanly free agents. Planets and stars don’t feel pain, don’t feel fear, don’t suffer. A billion stars could go supernova over billions of years and there would not be one tiny speck of pain, fear, anxiety, sorrow, or suffering.
God could have brought about the Earth and our solar system and the Milky Way through natural processes that took billions of years, and then when the right time came, he could have instantly populated the Earth by creating millions of animals and humans from nothing. No biological evolution required. Swinburne appears to be confusing cosmological evolution with biological evolution. But the former can take place without the latter taking place.
And God has the same reason for bringing about plants and animals-their beauty. And animals are good also, I have argued, in virtue not only of their beauty but also of their ability to have pleasant sensations and true beliefs and spontaneously to do good actions (even if not ones freely chosen). In view of all this, it is not too surprising that God should take the long (by our timescale) evolutionary route to produce human bodies. (EOG, p.188-189)
Again, these points are simply irrelevant. Grant for the sake of argument that plants and animals are beautiful, and that it is a good thing that animals exist because they can have pleasant sensations, true beliefs, and do good actions. So what? The question is not whether animals should exist, but what method a perfectly good deity would use to bring about such creatures. Since God is omnipotent (by definition, including Swinburne’s definition), God (if he exists) had the option to bring about plants and animals by a supernatural act of creation in which millions of plants and animals would be formed out of nothing in an instant.
Nothing in what Swinburne has to say here provides any sort of reason why we would expect God, an omnipotent and perfectly good person, to use a “long evolutionary process” which involves the pain, fear, suffering, and death of billions of animals over a billion years, when he had the option to instantaneously create every plant, animal, and human being that now exists.
If there was a God, then while it might be somewhat likely that God would bring about embodied humanly free agents, it is very unlikely that God would use the natural process of evolution to accomplish this end. Thus, the fact that embodied humanly free agents came into being as the result of the natural process of evolution appears to count against the existence of God, and certainly does NOT increase the probability that God exists, relative to the probability of God based purely on the evidence that there exists a complex physical universe that is governed by simple natural laws.
UPDATE at 2:30pm Pacific Time on 6/7/12:
Above, I said:
Premise (3) appears to me to have an obvious and serious problem. A key assumption behind most of Swinburne’s arguments for God is that it is somewhat probable (about .5) that God would choose to bring about the existence of embodied humanly free agents.
Someone paying close attention might notice that there is a shift in degree of probability from “somewhat probable” in the key assumption to “quite likely” in premise (3). This looks like a bad bit of reasoning by Swinburne, but there is a bit of logic that I left out of the picture.
Elsewhere in EOG, Swinburne points out that if there are multiple necessary conditions for God to bring about the existence of embodied humanly free agents, then each one of those necessary conditions must be more probable than the overall probability that God brings about the existence of embodied humanly free agents. This relates to the simple multiplication rule of probability.
If A and B and C must all occur in order for D to occur, and if A, B, and C are independent events (e.g. the occurence of A does not increase or decrease the probability that B will occur), then we can simply multiply the probabilities of A, B, and C to get the probability of D (assuming that A,B, and C are jointly sufficient to bring about D). If the probability of A is .8, and the probability of B is .8, and the probability of C is .8, then the probability of D would be .8 x .8 x .8 = .512 or about .5 (rounded to one significant digit).
So, if there are three or more necessary conditions for God to accomplish bringing about the existence of embodied humanly free agents, and if the probability is about .5 that God would bring about the existence of embodied humanly free agents, then the probability of each of the necessary conditions for God to accomplish this must be greater than .5 (unless all the other necessary conditions were certain and had a probability of 1.0).
The bringing about of bodies that have the features required for humanly free agents is just one out of at least a few different necessary conditions for the occurence of the sort of lives and interactions of humanly free agents that Swinburne envisions and that (allegedly) would provide God with good reason to bring about the existence of humanly free agents.