How we change what others think, feel, believe and do
Argument from Ignorance
Nothing is known about A. Yet a conclusion is drawn about A.
Facts may be given all around a particular subject, yet nothing specific is said about the subject. Based on this circumstantial evidence, it is assumed that something may be known about A.
A variant occurs where a lack of evidence is assumed to be proof, for example when a murder suspect does not have an alibi.
You live on Sunny Street. You have a gun. Nobody else on Sunny Street has a gun. There was a murder on Sunny Street last night. You were involved.
You live on Sunny Street. You have a gun. The person was knifed. You were not involved.
Circumstantial evidence is well known in the courtroom as being very weak evidence, if evidence at all. Yet in daily life it is used with impunity. Yet the notion of a person being innocent until proven guilty also makes conclusions without proof. Similarly, scientists largely assume something does not exist until it is proven (see Positivism).
A significant question with this is where the burden of proof lies. Is it with the prosecutor or the defendant? Usually it is with the person making a claim that something exists or has happened.
Also known as
Appeal to Ignorance, Burden of Proof, From Ignorance, Ad Ignorantium