Please non-believers, rebut this.

Great Debates
61

JS wrote:

Nothing. But then your first premise would be a non sequitur, and the conclusion would be invalid.

It’s saying “It is not necessary that God does not exist.”

“Possibility”. <>G is saying “It is possible that God exists.”

is modal necessity. <> is modal possibility.

~~G and <>G are equivalent expressions.

62

Why is that? I’m reading G->G as “thing G’s existence in actuality implies that thing G necessarily exists”. (“Thing G exists in actuality” -> “necessary existence of thing G”) Why would “the perfect ham sandwich’s existence in actuality implies that the perfect ham sandwich necessarily exists” be a non sequiter, whereas “god’s existence in actuality implies that god necessarily exists” is not? Is there an assumption about G:=god’s existence vs. G:=the perfect ham sandwich’s existence that I missed?

Again, honest questions. I’m not trying to give you a hard time.

63

Your first link contains this:

“Arthur Findlay, the great English psychic researcher who has very high credibility, stated that an eminent mathematician calculated that the odds of his medium getting by chance thirty four highly specific facts he got in just three readings was to 5 trillion to one.”

This is not evidence, it’s just laughable. :smack:

  • where is the evidence that Arthur Findlay is a ‘great researcher’?
  • where is the evidence that Arthur Findlay has ‘very high credibility’?
  • who was the ‘eminent’ mathematician?
  • why do you need an ‘eminent’ mathematician to calculate 2 to the power 34? Any 8 year old with a calculator could do it.
  • where is the proof that the medium was using communication with the dead, and that the only alternative was ‘chance’ and not a combination of cold and hot readings?( Have a look at www.ian-rowland.com to see how those work.)

Strewth, mate, if that is ‘strong’ evidence to you, I’d hate to see a weak case.

64

No problem. I can see how it might be confusing. But you have to keep in mind that the first premise works only because of how God is defined. That’s why the premise is justified as “from the definition”.

You can call G a ham sandwich if you wish, but by “ham sandwich”, you must mean Supreme Being, or necessary existence itself, and not what you ordinarily mean by ham sandwich. You can call it Guzzah, Hotspottle, or Acmenhouac, but you can’t mean anything other than necessary existence — otherwise it’s a fallacy of equivocation.

65

Incidentally, and tangential to what you’re asking, some people wonder why you can’t just throw out the whole tableau except for number (4): G -> G; that is, if God exists necessarily, then He exists in actuality. But you can’t just define something into existence, otherwise we could make pigs fly by redefining “fly” to mean “wallow in mud”.

A proper proof works from its hypotheses (not its definitions) to its conclusion. That’s why Peano did not have to define “successor” when he proved that 1 + 1 = 2.

66

While we’re dealing with an interesting argument, would you mind distinguishing “Necessary existence” from the universe?

And if we’ve only proven the existence of the universe logically, isn’t calling it God on par with calling it the ultimate ham sandwich?

67

The point you raise is popular among materialists who, honest but frustrated, are compelled to acknowledge the proof’s soundness. You may use the term “universe” if you wish, but the same rule of noneqivocation applies. You must mean “necessary existence” when you say universe, and necessary existence is metaphysical. This can be proved:

Hypothesis — For every x, it is necessary that there exists y, such that y = x.

  1. x = x. (Identity)
  2. For every y, such that y != x, x != x. (Quantification)
  3. If x = x, then it is not for every y that y != x. (2, Contraposition)
  4. If x = x, then there exists y, such that y = x. (3, Definition of existence)
  5. There exists y, such that y = x. (1 and 4, Modus ponens)
  6. It is necessary that there exists y, such that y = x. (5, Rule of Necessitation)
  7. For every x, it is necessary that there exists y, such that y = x. (6, Rule of Generalization)

QED

See An Account of Abstract Possible Worlds for a discussion on the metaphysics of actualism.

68

If God cannot be interacted with, God does not exist.

Interaction doesn’t require sensory stimuli.

69

Well said, Vorlon.

70

God was never defined in the proof, nor was G for that matter. I was taking G to be some given object. How is god being defined in this proof? The only definition offered was G, which I took to be “necessary existence (of G, some particular object)”. Would you clarify, please?

BTW, I thought the point of symbolic logic was that if a logical proof was true for a statement P:=x, then it was also true for a statement P:=y, where “:=” means “defined as”.

Why are these two statements not mutually exclusive?

71

JS wrote:

God was defined as Supreme Being (or necessary existence). From the original post with the proof:

Actually, in the 1990s, the ontological argument was, um, resurrected. By defining God as “Supreme Being”, you can use modal logic’s premises about necessary existence (necessary = supreme, existence = being) to develop a simple and eloquent modal tableau.

G was the hypothesis. From the original post with the proof:

Hypothesis: G (God exists in actuality)

That’s a bit scary. A term and its definition are equivalent expressions. Suppose I say that P = x, and use that to prove something. Should my proof also work if I define P = Not(x)?

The purpose of symbolic logic, as far as I’m concerned, is to map predicates.

The first premise is an axiom, not an inference.