1. The Classical Design Argument Inferring God’s Existence from “Design Features” of the Universe

2. Arguments for God’s Existence The project of developing arguments for God’s existence is typically designated natural theology. Theology – discourse about God Natural –a mode of discourse that engages the natural order, including both the human intellect and the physical cosmos. Hence, natural theology typically stands in contrast to revealed theology, discourse about God that proceeds from an analysis of the teachings of sacred scripture as a purported special kind of revelation from God.

3. Natural theology originated among Pre-Socratic philosophers in the 6 th century BCE in their effort to understand plurality and change as fundamental features of the cosmos. The most elaborate arguments are found in Aristotle’s Physics and Metaphysics. Origins in Western Philosophy Natural theology was appropriated by the Jewish and Christian religious traditions beginning around the 3 rd century CE and subsequently also by Islam shortly after its emergence in the 7 th century. Arguments for God’s existence were widely discussed throughout the medieval period, roughly from the time of St. Augustine (4 th -5 th century) to the beginnings of the European Renaissance in the 14 th /15 th century.

4. In the modern period, natural theology has been endorsed by the Catholic Christian tradition and many streams of Protestant Christianity. It has also been the subject of enduring philosophical exploration, as is reflected in the works of the great modern philosophers, e.g., Descartes, Leibniz, Hume, and Kant. Kant’s critique of natural theology in the 18 th century and the rise of Darwinism in the 19 th century generated significant skepticism about natural theology that continued until natural theology re-emerged in the middle of the 20th century as the result of developments in both philosophy and the sciences, especially cosmology.

5. The Classical Design Argument

6. “If, therefore, the products of nature are better than those of the crafts and if the crafts do nothing without the use of reason, then nature too cannot be held to be devoid of reason. “When you look at a statue or a painting, you know that craftsmanship was applied...when you gaze on a sundial or a waterclock, you understand that the time is told as a result of craft and not the result of chance. “So what sense does it make to think that the cosmos, which contains these very crafts and their craftsmen and all else besides, is devoid of deliberative ability and reason?” (Cicero, De Natura Deorum, 2.87)

7. The Stoic Argument (1)Whatever is ordered is intelligible. (2)Whatever is intelligible is a mind or the work of intelligence. So (3) Whatever is ordered is a mind or the work of intelligence. (4) The cosmos is ordered. So (5) The cosmos is mind or the work of intelligence.

8. The Design Argument John Ray (1628-1705) William Derham (1657-1735) William Paley (1743-1805)

9. The Watchmaker A watch is an intricate and complex system well-suited to the task of measuring time. We regard the watch as the product of some intelligent being on account of its complexity and functionality. Living organisms are intricate and complex systems well suited to the tasks of reproduction and survival. We should conclude that all living organisms originate from some intelligent being.

10. The Analogical Structure of the Classical Design Argument Objects of human contrivance exhibit complexity and purpose. The natural world exhibits complexity and purpose. The natural world has been designed by some intelligence. Objects of human contrivance have been designed by some intelligence. Similarity between objects of human contrivance and the natural world.

11. Philosophical Objections to Natural Theology

12. David Hume (1711-1776) In his famous Dialogues on Natural Religion, David Hume launched what is arguably the first systematic attack on both the design argument and natural theology in general. Cleanthes – the advocate of the Paley- style design argument Demea – an advocate of an alternate methodology, the cosmological argument, which seeks to prove God’s existence the fact of the universe’s existence, rather than its design features. Philo – the skeptic (more or less Hume’s own voice in the dialogue).

13. Objection 1: the Argument is a Weak Analogical Argument The design argument is an analogical argument and thus requires a degree of similarity between “human artifacts” and “the universe” which we are not warranted in assuming. Philo’s Criticisms of the Design Argument

14. Cleanthes’s Basic Argument: (C1) Houses are the product of intelligent design. Therefore, it is likely that: (C2) The Universe is the product of intelligent design. Philo’s Formulation of Analogical Arguments: (1) Object A has some property P. (2) Object A and object B are overall similar to some degree N. Therefore: (3) Object B has property P. Philo argues that the likelihood of (3) is directly proportional to the value assigned to N. The greater the similarity between A and B, the greater the likelihood that B has property P based on the fact that A has property P.

15. Hence, Cleanthes’s argument more precisely must take this form: (P1) Houses have the property of being produced by intelligent being. (P2) Houses and the universe are overall very similar to each other. Therefore: it is likely that (C3) The Universe has the property of being produced by intelligent design. Philo rejects (P2) and presents the following counter argument: (P1) Houses have the property of being produced by intelligent design. (P2*) Houses and the Universe are NOT overall similar. Therefore, it is unlikely that (C3) The Universe has the property of being produced by intelligent design.

16. I. Philo’s Argument for (P2*) – Dissimilitude Houses and the Universe are dissimilar because (a) we can observe houses being made and thereby link them to their causes through the constant conjunction of cause and effect, but (b) since the Universe is unique we have no basis to link it to any cause. II. Philo’s Defense of (P2*) We are not warranted in concluding that the cause of the whole universe is overall similar to the parts of the universe exhibiting reason or intelligence as their mode of operation. This is a fallacious inference (fallacy of composition) attributing to the whole what is characteristic of only selected parts of an imperfectly known universe.

17. Objection 2: We Cannot Infer “God” is the Designer Even if we are permitted to infer that the universe is designed, we cannot conclude that God is the designer. Philo’s First Objection depended on an assumption about causation, namely that we cannot postulate unobservable causes of observational phenomena, for cause and effect requires the constant conjunction of observable events. Philo’s Second Objection depends on another principle of causation, the principle of causal proportionality.

18. Principle of Causal Proportionality: We must not ascribe to a cause anything beyond what is minimally required to account for the effect. Theistic arguments violate this principle since they attempt to explain a finite, imperfect effect in terms of an infinite, perfect cause. Finite, Imperfect Universe Infinite, Perfect Being David Hume (1711-1776)

19. I.We cannot infer that the designer is infinite in power, knowledge, and goodness because only a being with limited power, knowledge, and goodness is required to produce a finite universe. II.We cannot infer that the designer is perfect because an imperfect designer would suffice to produce the universe, especially since (a) the universe exhibits many imperfections and (b) we know of many cases where designers are very imperfect (indeed, even stupid!) and yet despite this produce complex, useful, and beautiful things. III.We cannot infer that the designer is one because many agents working together or individually would suffice to produce the universe.

20. Philo’s second objection highlights the range of possible designer scenarios that would suffice for explaining design. Given that we have no principled way of selecting the more probable scenario from among the competitors, we can’t even infer that God probably exists.

21. Hume’s Dilemma Hume’s challenges to the design argument may be succinctly stated as a logical dilemma: 1. Either the designer of the universe is very unlike the universe or the designer of the universe is very much like the universe. 2. If the designer of the universe is very unlike the universe, then the degree of dissimilitude between the designer and the universe prevents actually inferring a designer of the universe. 3. If the designer is very much like the universe, then the degree of similitude between the designer and the universe prevents inferring that God is the designer of the universe. So: 4. Either we cannot infer a designer or we cannot infer that this designer is God.

22. Darwinian Scientific Objection

23. Prior to Charles Darwin, design arguments typically considered only two explanatory hypotheses for the complexity and adaptedness of living things.... The Chance Hypothesis The Design Hypothesis

24. With only chance and design as the competing hypotheses, the case for design seems very strong. It would be very surprising if purely random processes produced complex organisms well-adapted to the tasks of survival and reproduction. This datum is considerably less surprising if we suppose that living things have been designed.

25. Prime Principle of Confirmation Observational data, D, supports hypothesis H1 over H2 if D is more probable under H1 than it is under H2. Otherwise stated... If D is less surprising under H1 than it is under H2, then D evidentially favors H1 over H2.

26. Charles Darwin 1809-1882

27. Darwin succeeded in showing that complex forms of life could evolve from simpler forms of life through the biological law of natural selection operating on random variations thrown up by nature.

28. Three Explanatory Options H2: Solely Random Natural Processes H1: Intelligent Design H3: Darwinian Mechanisms D is surprising given H2, but not surprising given H1; however, D is equally unsurprising given H3. Let D = the existence of complex living things adapted to the tasks of reproduction and survival.

29. The Darwinian Objection Darwinism appears to undercut the design argument, as the hypothesis of biological evolution offers an at least equally likely explanation for the existence of complex living things.

30. “I have no need for that hypothesis.” - Pierre-Simon Laplace Laplace’s answer to the question posed to him by Napoleon Boneparte as to what place God had in his theory of the formation of the solar system. Is there a need to appeal to God to explain the universe?