QUETZALCOATL ITS REAL PROVE ME WRONG

because it is possible that evidence exists and we haven't observed it.

i.e. even with the premises:

(there exists the entity QUETZATCOATL) if and only if (there is evidence of QUETZATCOATL)

(evidence of QUETZATCOATL is observed by humans) implies (there exists evidence of QUETZATCOATL)

not(evidence of QUETZATCOATL is observed by humans)

there is not sufficient knowledge to deduce:
not(there exists the entity QUETZATCOATL)

i.e. if you construct the truth table there are cases where it is both true and false, and so it can not be said with certainty that it is true.

Ramuh was better.  Fuck FF8

QUETZATCOATL is Gilgamesh's main man. Gilgamesh and his posse gets shit done. Period.