I would suggest you read the following two posts:
http://lesswrong.com/lw/ih/absence_of_evidence_is_evidence_of_absence/ http://lesswrong.com/lw/mm/the_fallacy_of_gray/
I would suggest you read the following two posts:
http://lesswrong.com/lw/ih/absence_of_evidence_is_evidence_of_absence/ http://lesswrong.com/lw/mm/the_fallacy_of_gray/