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December 15, 2011


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Another proponent of the Prime Axiom.

"Axiom - Everything I believe is true. We can now procede to arguing my points."

I can actually see how someone can view "god exists" as the null hypothesis in this way. I don't agree, but I can understand.

What bothers me more is that there is no guidance on what to do with this information. By his own admission, Plantinga admits there is no proof of god. This means that god cannot have any effect on the world (otherwise we could measure the effect, which would constitute proof). If there is no effect, there is no rational argument for changing your behavior in resposnse to the god (there is no evidence of what change should be made). Thus, the rational reesponse is to behave as if there is no god whether you believe in one or not.

By the way, it's good to see you posting some more, Skeptico.

By the way, it's good to see you posting some more, Skeptico


I remember Plantinga. A few years back he was the darling of a certain segment of evangelicals who had discovered his version of the Ontological Argument. He had constructed it in modal logic, a somewhat obscure system that I, as a dude with a philosophy degree, have a hard time wrapping my head around. That says to me that your average fundagelical is just parroting it without really understanding it.

If they did try to understand it, though, they'd know that one of the axioms in modal logic states, essentially, that anything that is true in a possible world is true in all possible worlds. As an axiom it must be taken as true when utilizing modal logic but to me it seems like a pretty solid reason to avoid modal logic in the first place.

Apparently Plantinga just has a fetish for questionable axioms.

I grew up a catholic/christian(dad was christian ,mom was a catholic) but the more Ilearn the more I lean toward atheism,right now Iam more agnostic but leaning toward athiesm.ps love your stuff skeptico. you may like this youtube vid,its kinda funny and on topic.http://www.youtube.com/watch?v=dl6Z02TXZYw&feature=colike


Interesting video – thanks. That youtube is from April 2010. Here’s me on The Incredible Shrinking God from 2008.

I find your comment interesting Joe, the truth is that many more educated individuals in the fields of science especially are atheist than those who never learned these things. Mainly because the more you learn about the laws of physics, biology, chemistry or even just learning to think critically it becomes harder and harder to imagine religeon of any kind being true.

Don is completely incorrect. The system of modal logic is called S5 and it's not very difficult to understand (within the realm of logic--Don is right in that logic in general can be tough to wrap your head around). It's elementary modal logic, learned in a typical undergraduate logic course and in the first week or two in a graduate course.

The axiom does NOT say that if something is true in one possible world then it's true in all possible worlds. That's obviously stupid, since there's a possible world in which Barack Obama isn't the president, but that isn't true in this world. So no, that's not an axiom in ANY system of modal logic that I'm aware of.

The actual axiom in S5 says that if something is possibly necessarily true, then it is necessarily true--i.e., if it is possibly true in ALL possible worlds, then it is true in all possible worlds. It's formally represented as <>[]P-->[]P. I could draw you models on a napkin and prove it.

I'm an atheist, I think Plantinga is wrong about nearly everything, and his version of the ontological argument is question-begging (what atheist would accept the premise of the possibility of God's necessary existence?). But it's upsetting to see basic logic abused on a website that is supposedly dedicated to logic and rationality. No offense Don, but modal logic is a completely legitimate subject that you are attacking based on a complete misunderstanding of it.

I am utterly culpable for that misunderstanding and it makes me feel dumb to have misinterpreted things so poorly. At the same time, I would appreciate it if you would not condescend to me. Your understanding of modal logic is obviously superior to mine but I happen to have a philosophy degree and never once covered modal logic in any formal logic course. Hell, I only ever even heard of it thanks to Plantinga. My various phil major friends, with degrees from universities in different parts of the country, likewise never covered modal logic in their coursework. I know this because it has come up in conversation. So thank you, in all honesty, for the correction and I will definitely not make that mistake again. I feel like a dumbass for making it in the first place. But your assumption that anyone who took a basic logic class should understand this is clearly not correct.

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