The God Of Logic

Is it possible to prove God through observation and logic? Some people believe it's possible and some people believe otherwise. In the first group are many of God's apologists while on the other side are atheistic thinkers and theists who rather base their worldview on faith than on reason For these believers trying to use reason to prove God is heresy as that is an attempt to cover God with the human mind. Aquinas, while offering his own evidence for the existence of God, criticizes Anselm and his ontological argument for proving God using logic alone. Many theistic thinkers have sought to improve Anselm's argument and one of the most used versions today is the modal ontological argument of Alvin Plantinga, which is based on system S5 of the modal logic. Is it possible to prove God through observation and logic? I will take Anselm's formulation written in modern language. If I commit an error in the formilation I hope you understand it to be a homest mistake, not that I'm introducing a straw man to refute. Anselm of Canterbury tells us that: 1. Our understanding of God is a being than which no greater can be conceived. 2. The idea of God exists in the mind. 3. A being which exists both in the mind and in reality is greater, provided same conditions, than a being that exists only in the mind. 00:01:13.35,00:01:16.50 4. If God only exists in the mind, then we can conceive of a greater being than God. 5. We cannot be imagining something that is greater than God. 6. Therefore, God exists. I can see to possible reactions in people like me, who are not experts in logic and rhetoric: it either sounds convincing or not. In great extend, how convincing the argument sounds comes from our presumptions and therefore are these presumptions, rather than the rhetoric, which lead us to conclude either God exists or not; or either Anselm's argument is conclusive or not. When the validity of an argument seems to depend on our presumptions we are probably facing a formal fallacy called begging the question (petitio principii), of which a common example is circular argument. I have used, and I will keep using, “rhetoric” in the broadest sense as the art of persuation through logical arguments. Sometimes the term is used as the art of deceive or mislead using intentional fallacies; but this is only part of the broader sense. A good argument, a well-founded rhetoric is the one that does not use formal or informal fallacies and persuades. However, rhetorics is not reality. A good argument is not one whose conclusion is true. A conclusion night be a proposition in line with reality while the argument be fallacious, or an argument can be consistently following the premises (a good argument), but not be in line with reality (usually because a premise is not in line with reality). Anselm's argument begs the question (formal fallacy) and fails to convincingly define God (informal fallacy). I will not refute it as many people have already done it, including the same apologists who wanted to improve the ontological argument: you only attempt to improve an argument that is fallacious. I now present the modal ontological argument by Alvin Plantinga, which is based on modal logic, particularly on the fifth axiomatic system of modal logic, or S5. The argument is as follows: 1. A being has maximal excellence in a given possible world W if and only if it is omnipotent, omniscient and wholly good in W; (a definition) and 2. A being has maximal greatness if it has maximal excellence in every possible world. (another definition) 3. It is possible that there is a being that has maximal greatness. (This is a premise) Therefore, an omniscient, omnipotent and perfectly good being exists. 4. Therefore, possibly, it is necessarily true that a maximally excellent being exists. 5. Therefore, it is necessarily true that a maximally excellent being exists. 6. Therefore a maximally excellent being exists. As God is defined as the maximally great being, it is proven that God exists. The first time I saw a version of the modal ontological argument (without the axiomatic explanations and without a deep knowledge of what modal logic is) I had, more or less, the same reaction that with Anselm's argument: it is not convincing, it only uses a more twisted rhetoric so that it is more difficult to refute. Most attacks against Patinga's argument are similar as refutations against Anselm's argument. Most defenders of the modal argument critizize these refutations pointing on ignorance on modal logic. In my perception, Platinga does not improve substantially Anselm's argument but just dresses it in a more sophisticated dress There are three points I raise on Alvin Plantinga's modal ontological argument: 1. The premise (3) is debatable. 2. Conclusion (5) depends on an axiom. 3. Rhetoric is not reality. I have seen many attempts to prove and refute if maximal excellency, as it is defined here, is possible in this world. One example is the omnipotency paradox: “Can an imnipotent god create a stone so heavy he could not move?” o the existence of evil infront of the three omni; as well as justifications or solutions to these arguments. So far I'll tell that that is a debatable concept and I won't expose my position's arguments. But when we add necessity as part of the definition for maximal greatness, we are somehow begging the question. Admitting necessity as a rhetoric feature implies that modal logic is being used as support of modal logic which leads us to the paradox of an self sustented axiomatic system. When Greek geometer Euclid formulated his treatise on geometry Elements, he stablished the existence of three sorts of truths: Axioms which are self-evident truths. Postulates which cannot be proven but are truth, and Theorems, which can be proven from axioms, postulates and previously proven theorems. In Elements Euclide formulated the axioms and postulates of geometry, but one of the postulates, Euclid's Fifth Postulate, was subject of debate until 19th century when Bernhar Riemann proved that the Fifth Postulate could be negated and yet we have an internally consistent geometry. Observations that we have mate to the Universe show us that space is not Euclidean. Euclidean geometry, while yet is useful in science and engineering, has a limited scope if we want to describe that whole known reality that is the observable universe. In current understanding in formal sciences, such as Mathematics and Logic, an axiomatic system (term “postulate” is not currently used) is consistent if it does not internally contradict and no axiom can be inferred from the other axioms. If an axiom is negated you have another coherent axiomatic system (If you don't, the negated axiom is not independent and has been proven ad absurdum as a theorem). A theorem is true only in an axiomatic system. That same theorem may be false or unprovable in another axiomatic sytem. S5 modal logic is consistent, but is not the only possible logic. A theoreme in S5 tells us that if something can be necessarily true (is necessarily true in a possible world) then it is necesarily true (is true in every possible world). If I negate the Euclidean accessibility axiom from S5, I will still have a coheren system of modal logic, but I will not longer prove God. Euclidean geomery is useful. For most human experience the geometry Euclides described in 3rd century B.C.E. is enough and many non-Euclidean geometries can be described using Euclidean geometry, replacing terms such as plane for spherical surface and line for great circle. Most engineering and applied cience today is based on Euclidean geometry and Newton's mechanics. But both Euclid's geometry and Newton's mechanics fail to describe quantum mechanics or relativity theory. When we step out human experience scale, what was for Euclid self-evident truths are not longer valid. We can validate a system of thought such as Mathematics or Physic laws By its usefulness, and the same happens with rhetoric. S5 modal logic may be useful. What does it means a logic system is useful? A logic is usefull if from “true” premises we can inferr a “true” conclussion. But “true”, according to current science epistemology, means something with pretictability that has not yet been proven false. A rhetorical approach that use a consistent logic and bring us to a conclussion from some premises, does not proves that conclussion is true: it proves that the conclussion is correctly inferred. Accepting modal logic with the Euclidean property and accecpting premise that maximal greatness is possible (and accepting that it is valid to include necessity in the definition), Plantinga's modal ontological argument does not proves God but maks God dependent of a premis with no predictive value. Alvin Plantinga does not offer a brand new and consistent logical approach to prove God. He basically brings a more fancy dress, called modal logic, to Anselm's argument which is diluted in the premisse: to define maximal greatness with existense (or as necessary existance) as a possible feature. Now: refuting an argument does not imply refuring the conclussion. I cannot say that God does not exists because Anselm of Canterbury's logic, or Alvin Planinga's logic are fallacious. I only say that inferrence is not sound. However my refutation is derived from certain principles, from certain presupossitions by myself. It comes from defining truth under current science epistemology: propositions with predictive capacity that have not been proven false yet. If your conception of truth differes, then my refutation will not be convincing. But that's for another video.