In February I posted on David Buss being convinced that "true love" exists, even though he’s never seen it and his job is to study love. Similarly, Michael Murrin tells (p.11) how Europeans were immune to being told by Marco Polo how real unicorns (rhinoceroses) differed from what they had imagined:
Marco Polo was careful to disabuse Europeans of various fictional marvels that they then accepted as fact or which had considerable popular support. One case provides a good example. It concerns unicorns. Polo saw rhinoceroses in Indonesia and described them minutely. He ended his discussion with the remark that such unicorns do not resemble at all European notions, nor do they allow themselves to be captured by a virgin. Yet despite the fact that the Divisament dou monde had wide circulation and multiple translations, even while Polo was alive, his attempt to dispel or correct such European fantasies failed. The unicorn survived in tapestries like the great series now shared between New York and Paris and in the spiral horns of the narwhal that resembled the European idea of the unicorn’s horn and can still be found in princely collections.
I’ll bet many who study politicians, celebrities, and scientists similarly believe that ideal versions of these types exist somewhere, even if they have never actually found any examples in their studies. It seems that once we imagine some ideal we have a strong need to believe it exists somewhere, even against all evidence.
I will use only the strictest first-order logic to form my deductive chain, which is modeled on the proof that "P and ~P implies Q". First, the source material from which I take my axioms:
"God is not a man, that he should lie; neither the son of man, that he should repent: hath he said, and shall he not do it? or hath he spoken, and shall he not make it good?" -- Numbers 23:19 (KJV)
Interpreted literally, we can state that "God can not change his mind." Let this be Axiom A.
"And the LORD repented of the evil which he thought to do unto his people." -- Exodus 32:14 (KJV)
Interpreted literally, we can state that "God can change his mind." Let this be Axiom B.
Update: Before we go any further, I'd like to address some potential points of contention. The KJV is a horrible, horrible translation -- as Jon notes below, when properly translated, the first quote I mention doesn't lead to Axiom A. But there are plenty of places in the Bible that lead to contradiction, either directly or indirectly. I'm just using this particular pair of quotes as an example -- I'm sure somehow more well-versed in the Old and New Testaments could find a much better pair. [more?]
1. Introduce Axiom A: God can not change his mind.2. Introduce Axiom B: God can change his mind.3. Enter hypothetical on the base of "Unicorns do not exist."1. First line of hypothetical: Unicorns do not exist.2. By statement 1: God can not change his mind.Conclusion of hypothetical: If unicorns do not exist, then God can not change his mind.4. Contrapositive of statement 3: If it is not true that God can not change his mind, then it is not true that unicorns do not exist.5. Cancel double negative: If God can change his mind, then it is not true that unicorns do not exist.6. Cancel double negative: If God can change his mind, then unicorns exist.7. By statements 2 and 6: Unicorns exist.
The result is that in any system where the statements "God can change his mind" and "God can not change his mind" are both true, unicorns must exist. (Incidentally, the same logic can be used to prove that unicorns do not exist. Slippery beasts, eh?) In fact, any statement of fact can be used instead of "Unicorns (do not) exist", including "1 equals 2" or "Tim is God" or "Thou shalt kill" -- that is the power of direct contradiction. Thus it is shown that if you believe the Bible (or Quran or Torah) word-for-word, you'll believe anything.
Mobile, Joe,
You guys may be interested in looking up Hempel's "all crows are black" paradox: if you see a non-black non-crow, e.g. a red apple, is that evidence for the the statement "all crows are black"?
In the philosophical literature, there are different solutions proposed for this. Personally, I'm ok with saying "yes, it is".