Negative Evidence

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

~ "Silver Blaze", by Sir Arthur Conon Doyle

INDEX ......................................

Negative Evidence - Richard Levin

"The first point is that we cannot hope to prove any proposition unless we look for negative evidence that might contradict it, and the second point is that many of us ignore the first point, because of the tendancy of our minds (not, of course, of "human nature") to look only for positive evidence that confirms a proposition we want to prove. This tendancy explains the remarkable tenacity of superstitions ... and of prejudices ....

p.389

The third basic point ... We must recognise, not only that we cannot hope to prove any proposition unless we look for negative evidence that might contradict it and that we have a tendency to look only for positive evidence, but also that we cannot hope to prove any proposition unless this negative evidence could exist. The principle is well known to scientists and philosophers of science, who call it disconfirmability. They insist that if a proposition does not invite disconfirmation, if there is no conceivable evidence the existence of which would contradict it, then is cannot be tested and so cannot be taken seriously. If it is not disprovable, it is not provable.

p.409

When combatants encounter an argument, they do not ask about the evidence for or against it; they just ask if the argument is for or against their side, since they believe ... that "the only real question ... is: Which side are you on".

... we not only tend to overlook or forget negative evidence that contradicts our beliefs, but when others point such evidence out to us, instead of thanking them for this chance to correct our beliefs, we tend to get angry with them, and this anger increases in direct proportion to our commitment to the beliefs.

The Dog in the Night-Time: Negative Evidence in Social Research - George H. Lewis and Jonathan F. Lewis

Abstract

The overwhelming emphasis in social research on collecting positive data has had the dangerous effect of minimizing the worth of negative evidence, which is defined in this paper as either
(1) the non-occurrence of events,
(2) an occurrence that is not reacted to or not reported (because it is outside the frame of reference of the population or of the researcher), or
(3) although noted in its raw form, distorted in its interpretation or withheld from analysis and report.

A paradigm of seven types of negative evidence is developed:

(1) Events Do Not Occur;
(2) Population Is Not Aware of Events;
(3) Population Wishes to Hide Events;
(4) Commonplace Events Are Overlooked;
(5) Effects of the Researcher's Idea Set;
(6) Unconscious Non-Reportage; and
(7) Conscious Non-Reportage.

Each type is discussed, and examples are presented. The paper concludes with a discussion of the place of negative evidence in both inductively and deductively based social research, and a caution against ignoring such data.

Falsifiability

For example, the assertion that "all swans are white" is falsifiable, because it is logically possible that a swan can be found which is not white. Not all statements that are falsifiable in principle are falsifiable in practice.[1] For example, "it will be raining here in one million years" is theoretically falsifiable, but not practically so.

The concept was made popular by Karl Popper, who, in his philosophical criticism of the popular positivist view of the scientific method, concluded that a hypothesis, proposition, or theory talks about the observable only if it is falsifiable.

Unindexed Notes/References:

http://www.delawgroup.com/dth/?page_id=452 Delaware Trial Handbook § 20:12. NEGATIVE EVIDENCE “Negative evidence” is testimony that an alleged fact did not exist or that an alleged event did not occur. There may be in an issue in a case, for example, as to whether a bell rang or a horn sounded or whether something could or could not be seen. To prove the absence of such sight or sound, testimony may be offered by witnesses who did not see or hear the alleged sight or sound. Negative evidence is admissible if it is relevant.138 Whether it is relevant will depend on whether a witness had the opportunity to observe the event. If it is determined that the evidence is relevant and so admissible, then it becomes a question for the trier of fact to determine what weight should be given to the testimony. [PDF] How Convinced Should We Be by Negative Evidence? www.psych.unito.it/csc/cogsci05/frame/poster/2/f416-hahn.pdf File Format: PDF/Adobe Acrobat - Quick View by U Hahn - Cited by 15 - Related articles Should all arguments from negative evidence be avoided, or can a systematic ... the difference between positive and negative evidence and allows one to ... NB"Bayesian exquations [PDF] Formalization of Evidence: A Comparative Studyjournal. agi-network.org/portals/2/issues/JAGI_1_25-53.pdfYou +1'd this publicly. Undo File Format: PDF/Adobe Acrobat - Quick View by P Wang - 2009 - Cited by 5 - Related articles positive and negative evidence (though sometimes they are called by other ... black ravens are negative evidence, and non-ravens are irrelevant (Hempel, ... I'm reading through Michael Martin's "The Case Against Christianity" , & in the chapter on the historical jesus he puts forth what he calls the 'negative evidence principle' He outlines it as follows: A person is justified in believing that p is false if (1) all the available evidence used to support the view that p is true is shown to be inadequate and (2) p is the sort of claim such that if p were true, there would be available evidence that would be adequate to support the view that p is true and (3) the area where evidence would appear, if there were any, has been comprehensively examined

Thesis | Arnaldo Momigliano | Mountain Man