Quotes / Absence of Evidence

Gregory: Is there any other point to which you would wish to draw my attention?
Holmes: To the curious incident of the dog in the night-time.
Gregory: The dog did nothing in the night-time.
Holmes: That was the curious incident.

"What tipped me off was the lack of evidence."
Batman, Justice League

Faith: So you think there's some big conspiracy?
Buffy: (looks in filing cabinet to find all the files are empty) You were saying?
Faith: So those papers are gone. That doesn't prove anything.
Buffy: Except that someone didn't want us to prove anything.
Buffy the Vampire Slayer, "Consequences"

Donna: The first thing I noticed is an empty file.
The Doctor: Why, what's inside it? Or, what's not inside it?
Donna: Sick days. There aren't any. Hundreds of people working here and no one's sick. Not one hangover, man flu, sneaky little shopping trip, nothing. Not ever! They don't get ill!
Doctor Who, "The Sontaran Stratagem"

'"So the moon is 6.3 billion years old, and the source cited is the author's ass!"'

http://tvtropes.org/pmwiki/pmwiki.php/Quotes/AbsenceOfEvidence