Arbitrary Skepticism/Playing With

Basic Trope: A character in a world where strange things happened finds it difficult to believe in another strange thing
 * Straight: Bob uses magic every day but refuses to believe in unicorns.
 * Exaggerated: Flat Earth Atheist.
 * Justified:
 * Bob has proof of magic, and expects the same amount of evidence for unicorns.
 * Bob lives in an Urban Fantasy world where magic is common knowledge and an integral part of society, and is thus used to it. Unicorns, on the other hand, are something no one's ever seen.
 * Bob assumed someone used magic to make unicorns then claim they have always been real.
 * Inverted: If Jesus, Then Aliens.
 * Subverted: Bob finally agrees to believe in unicorns when presented with the proper amount of evidence.
 * Double Subverted: Bob was only claiming to believe in them to get people to shut up.
 * Parodied: Bob believes in dragons, but will rant on at length about how green dragons are impossible, and every green dragon seen thus far was painted that color.
 * Deconstructed: The world's magic runs on Clap Your Hands If You Believe; Bob's refusal to believe in unicorns without evidence spreads until they are driven extinct.
 * Reconstructed: However, once Solipsist Steve points out to Bob that he erased a perfectly real creature because he spitefully refused to allow for the possibility it existed, he is forced to realize he wasn't being a skeptic but a dogmatic. He then reaffirms his willingness to believe unicorns exist and not be a pure naysayer.
 * Zig Zagged: Bob doesn't believe unicorns exist just because dragons do, but his bias is because he thinks unicorns are girly and stupid, but he admits he would still disbelieve in the existence of unicorns even if they were awesome robots.
 * Averted: When informed of their existence, Bob easily accepts unicorns as real.
 * Enforced: The author wants to put a Masquerade in a fantasy setting.
 * Lampshaded: "You're right, unicorns are crazy. As crazy as that magic crystal ball you've been using."
 * Invoked: "Yes, magic is real. That's no reason to stop being a skeptic."
 * Defied: After seeing the impossible once, Bob decides to believe anything he hears as long as it comes from a trusted source.
 * Discussed: "Just because we've proven several myths have basis in fact (if not literal truth) doesn't mean All Myths Are True."
 * Conversed: "Ooh, poor Bob. Doesn't he know skeptics always die in Horror movies?"

Just because there's a main page for Arbitrary Skepticism doesn't mean it's possible to go there! Why don't you prove it then?