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Does God Exist? Nature of God The four qualities of God (for our purposes): 1. Omnipotent (all powerful) 2. Omniscient (all knowing) 3. Omnibenevolent (perfectly good) 4. Creator of the universe Nature of God This is only one concept of God, but it seems to be the notion of God advocated by the Judeo-Christian family of religions. Nature of God This constrains what counts as a good argument for God’s existence. (1) Cosmological Argument (2) Pascal’s Wager Cosmological Argument Cosmological Argument (1) Every event must have a cause. (2) The causal chain cannot be infinite. (3) Therefore, there must have been a first cause. (4) Therefore, God exists. Cosmological Argument Does the existence of a first cause mean the first cause must be God (in our sense)? Why not a very very powerful but not omnipotent creator? Why not a mostly but not perfectly good creator? Why not a coalition of creators? Why does the first cause have to be conscious at all? Even granting all the premises, this argument does not establish that God (in our sense) exists. Pascal’s Wager Pascal pointed out that there are four exhaustive possibilities regarding God’s existence and your belief: 1. 2. 3. 4. God exists and you believe that God exists God exists and you do not believe that God exists. God does not exist and you believe that God exists. God does not exist and you do not believe that God exists. Pascal’s Wager God Exists Believe in God Don’t believe in God God does not Exist Pascal’s Wager Pascal’s Wager God Exists Believe in God Don’t believe in God God does not Exist Pascal’s Wager Pascal’s Wager God Exists Believe in God Don’t believe in God God does not Exist Pascal’s Wager Pascal’s Wager God Exists Believe in God Don’t believe in God God does not Exist Pascal’s Wager Two (of many) problems with this argument: First, the existence of Hell seems incompatible with the idea of a perfectly benevolent, all-powerful deity. Not so bad. We can revise the argument slightly to say, if you don’t believe you just don’t get into heaven. You still lose out infinitely by not gaining an infinitely good reward, so the wager will still work. Pascal’s Wager The second more serious problem is that the argument does not only work for God as we have defined the term. Zeus’ Wager Zeus Exists Believe in Zeus Don’t believe in Zeus Zeus doesn’t Exist Zeus’ Wager Both Zeus and the Judeo-Christian God are jealous, so if you believe in the wrong one you go to hell. You can run the same argument for a potential infinity of jealous deities. Paley vs. Dawkins: The Teleological Argument Why They Failed The two arguments we looked at last time failed because they did not establish that a being with the following properties exists: Omniscience Omnipotence Omnibenevolence Even if they show that we should believe in something, they don’t tell us what. Preliminaries “Telos” is translated from Greek as purpose, end, or goal. Preliminaries Teleological arguments for the existence of God purport to show that God must exist because the universe (or some feature of it) could only have been brought about by the hand of a conscious being. Preliminaries Usually their structure is to point to one or more structures in the universe that seem to be designed and argue that design implies a designer. Preliminaries Paley’s famous argument epitomizes two argument forms we haven’t yet discussed: 1. Argument by analogy 2. Inference to the best explanation Non-Deductive Arguments Deductive arguments go wrong when: 1. One or more of the premises are false (or poorly supported) 2. The premises do not entail the conclusion 3. The argument commits some fallacy or other (e.g. circular reasoning) Argument by Analogy An argument by analogy is a non-deductive argument of the following form: 1. X has feature A. 2. X is relevantly similar to Y. 3. Therefore, Y has feature A. Argument by Analogy Ways for an argument by analogy to fail: 1. The two compared phenomena are not that similar 2. They are similar in some ways, but different relevant to the feature under consideration 3. The similarity between the two kinds of things is superficial, and not supported by looking at a wider sample size 4. There are unintended consequences to the analogy. Inference to the Best Explanation Inference to the best explanation is another kind of non-deductive argument of the following form: 1. X is an observed phenomena. 2. If Y were the case, then it would best explain why X is the case. 3. Y is the case. Inference to the Best Explanation You are walking on the beach and see two sets of shoeprints next to one another, one set of adult size, and one significantly smaller. You conclude that the footprints are those of a parent and a child because this best explains the data you have. Inference to the Best Explanation Inference to the Best Explanation 1. 2. 3. 4. Power Elegance Simplicity Consistent with proven explanations of other similar observations 5. Fits into an explanatorily useful theory 6. Etc. The Watch We walk through the woods and come across a watch. What conclusions should we draw about this thing? The Watch The object has certain features: 1. The parts are all arranged in a manner that produces a certain motion. 2. If the parts were of slightly different physical form, the motion would not occur. 3. If there were missing or different parts, the motion would not occur. 4. If the parts were arranged differently the motion would not occur The Watch Paley claims that the best explanation of these features is that the object has a purpose, and that it was designed by some intelligent entity to fulfill that purpose. The Argument from Analogy Living organisms share all of these qualities: 1. The parts are all arranged in a manner that produces a certain motion. 2. If the parts were of slightly different physical form, the motion would not occur. 3. If there were missing or different parts, the motion would not occur. 4. If the parts were arranged differently the motion would not occur The Argument from Analogy Paley’s Argument 1. Watches have complex features the best explanation of which is that the watch was created by an intelligent designer for some purpose. 2. Living organisms are similar to watches in these respects. 3. Therefore, the best explanation of the complexities that we find in living organisms is that living organisms were created by an intelligent designer for some purpose. Disanalogy #1 We know how a watch is constructed, but we do not know how a human is constructed. 1. Do we know this about the watch (you and me?) 2. Would it matter? What if we happened across some advanced alien technology? Some lost art of ancient people? Disanalogy #2 We know the purpose of the watch but we do not know the purpose of living things. We don’t need to know particular purpose of an artifact to know that it was designed for some purpose or other. The same goes for individual parts of the watch Disanalogy #3 Watches do not duplicate themselves, organisms do. Paley argues that if the watch were able to do this it would simply be more evidence of design, and cause for greater respect for the designed. Would make it likely that the first watch we observed was not the original, but this should not affect our conclusion that there was some original watch, that was designed by an intelligent designer. Summing Up “There cannot be design without a designer; contrivance, without a contriver; order, without choice; arrangement, without anything capable of arranging; subserviency and relation to a purpose, without that which could intend a purpose; means suitable to an end, and executing their office in accomplishing that end, without the end ever having been contemplated, or the means accommodated to it.” (11) Summing Up “There cannot be design without a designer; contrivance, without a contriver; order, without choice; arrangement, without anything capable of arranging; subserviency and relation to a purpose, without that which could intend a purpose; means suitable to an end, and executing their office in accomplishing that end, without the end ever having been contemplated, or the means accommodated to it.” (11) For Next Time Read the interchange between Anselm and Guanilo, (22-32 in the reader) A Problem? Does the teleological argument suffer from the same flaw as the cosmological argument did? Suppose we grant that there must be a designer. Why must that designer be God? A Problem This is definitely an issue that needs to be addressed, but there are things that can be said: Only an omnipotent Creator would have the power to bring into existence the vastness of the universe. Only an omniscient Creator could have set things up to work in such perfect harmony creating galaxies, solar systems, stars, planets, etc. Dawkins on the Design Argument Complexity and Explanation Any kind of complexity is statistically unlikely and demands explanation. The best kinds of explanations of complex phenomena explaining the complexity in terms of simpler phenomena. Complexity and Explanation Design explanations of complex phenomena should be a theoretic last resort, at least in the absence of direct evidence of design (e.g. you watch someone make a watch) The Prometheus Problem In general, explaining complexity by reference to equally or more complex phenomena just causes us to demand an explanation of the greater complexity. The Prometheus Problem Just like it doesn’t help to explain the origins of life by talking about aliens seeding life on earth, it doesn’t seem to help explain complexity (biological and otherwise) by appealing to God. The Prometheus Problem Dawkins points out that God seems to be the most complex thing around. Thus, an appeal to God to explain a bit of complexity that baffles us, is not much of an explanation at all. Natural Selection Natural Selection: The process by which organisms with genotypic traits that make them better suited to their environment tend to survive, reproduce, and increase in number. Natural Selection Phenotype: Observable traits of an organism. E.g. form, structure, development, behavior, physiological properties, etc. Genotype: Genetic traits of an organism. Inherited genetic code. Natural Selection 1. Copying errors in the reproduction of the genetic code (mutations) result in different genotypic traits. 2. These genotypic traits may result in different phenotypic traits. 3. If the new phenotypic traits are beneficial, they promote survival and reproduction of the organism and thus are reproduced in the next generation. 4. If the phenotypic traits are malignant, they are selected against. Natural Selection: A Better Explanation Natural selection doesn’t have the Prometheus problem that the design hypothesis has because it explains complexity in terms of simpler entities. Natural Selection: A Better Explanation Why it is a better explanation than design: 1. Power: it explains how all complex traits of living organisms arose 2. Elegance: it does so by use of a single overarching principle (NS). 3. Simplicity: Does not posit additional entities beyond those of the natural world 4. Reductive: Explains the very complex by making reference only to successively simpler elements. Irreducible Complexity This is an empirical theory that (like all such theories) may be falsified. One way this could happen would be for us to discover some kind of complex structure in an organism that could not be explained by the process of natural selection Such a trait would be an instance of irreducibly complexity (IC). Irreducible Complexity Possible examples: the eye, the nervous system, the flagellar motor, a bird or insect’s wing, etc. Even if these have evolutionary explanations (which they do), it is possible that some genuine example of IC could be found. Irreducible Complexity Two things to remember about all such examples: 1. No candidate has yet been offered that has stood up to serious scrutiny and protracted investigation. 2. The bar is low for the biologist: all she has to show to respond to the objection is that natural selection could have produced the trait in question. Fine-Tuning It turns out that if certain fundamental features of the universe (e.g. the force of gravity, the amount of energy in the universe at its creation) were only very slightly different, then life would have never developed. Announcements The course website is phil1ucsb.wordpress.com. For next time read Rowe’s “The Problem of Evil and Some Varieties of Atheism” Fine-Tuning Newton’s Law of Universal Gravitation: G= 6.67384 x 10-11 m3kg-1s-2 Fine-Tuning Given that a relatively small number of the infinite possible values for these features would be amenable to life as we know it, it seems like some basic features of the universe were fine-tuned to allow for life to develop. God of the Gaps We don’t currently have an explanation for the observed values of the cosmological constants, and there are unanswered questions in evolutionary biology (e.g. the origins of life) God of the Gaps Both the irreducible complexity and the fine-tuning arguments make use of what Dawkins calls “the God of the Gaps” argument. (1) There is some gap in our naturalistic/scientific understanding of the world. (2) Therefore, the correct explanation of this phenomena must be supernatural (e.g. God) God of the Gaps: Problems 1. Science has historically been very good at filling the gaps. (e.g. alleged examples of IC like the wing, the eye and the nervous system). 2. The current lack of a scientific explanation of some physical phenomena does not suggest that one will not be given at a later date. 3. Even if current naturalistic theories cannot explain a feature of the universe, the default view should not be the design hypothesis. When a scientific theory fails, the response is to look for a new theory! 4. Current gaps in understanding should encourage us to find answers to our questions. God of the Gaps: Problems From Dawkins: “If you don’t understand how something works, never mind: just give up and say God did it. You don’t know how the nerve impulse works? Good! You don’t understand how memories are laid down in the brain? Excellent! Is photosynthesis a bafflingly complex process? Wonderful. Please don’t go work on the problem, just give up and appeal to God. Dear scientist, don’t work on your mysteries. Bring us your mysteries, for we can use them. Don’t squander precious ignorance by researching it away. We need those glorious gaps as a last refuge for God.” (24) God of the Gaps: Rejoinder Isn’t some explanation better than no explanation? Right now, science cannot explain these things but the theistic hypothesis can. Isn’t it reasonable, right now, to believe in God given our evidence? God of the Gaps Sometimes it is better to not believe any explanation. If the evidence does not positively support any particular explanation, then the correct attitude to take is to suspend judgment on the matter. God of the Gaps There are deep mysteries about the universe that we do not yet understand. But it is precisely because of our deep ignorance about things like the origins of life or the reasons for the deepest structural features of the universe that we should not base any beliefs on these matters.