Difference between revisions of "Rational evidence"

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'''Rational evidence''' is the broadest possible sense of [[evidence]], the [[Bayesian]] sense; rational evidence about a hypothesis H is any observation which has a different [[likelihood]] if some hypothesis H is true or alternatively false.
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'''Rational evidence''' is the broadest possible sense of [[evidence]], the [[Bayesian]] sense.  Rational evidence about a hypothesis H is ''any'' observation which has a different [[likelihood]] depending on whether H holds in reality or not.
  
Rational evidence is distinguished from narrower forms of evidence, such as scientific evidence or legal evidence.  For evidence to be scientific, it must be, in principle, publicly accessible; you should be able to do an experiment to verify the knowledge.  For evidence to be admissible in court, it must meet other legal standards.
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Rational evidence is distinguished from narrower forms of evidence, such as scientific evidence or legal evidence.  For a belief to be scientific, you should be able to do repeatable experiments to verify the belief.  For evidence to be admissible in court, it must e.g. be a personal observation rather than hearsay.
  
For example, suppose I tell you that the original author of this paragraph wore white socks while writing it.  (In fact, I do so tell you.)  You now have ''rational evidence'' that the author of this paragraph wore white socks.  But it is not ''scientific evidence'' because there is no experiment you can do for yourself to see whether it is true.  And it is not ''legal evidence'' - you could testify in court that I had ''told'' you my socks were white, but you could not testify that my socks were white unless you had observed it for yourself.
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For example, suppose I tell you that the original author of this paragraph wore white socks while writing it.  (In fact, I do so tell you.)  You now have ''rational evidence'' that the author of this paragraph wore white socks, because I'm more likely to tell you this if I am wearing white socks, than if I'm not (Note: This doesn't prove that I am wearing white socks; this is why it is 'evidence').  But it is not ''scientific knowledge'' because there is no experiment you can do for yourself to verify whether it is true.  And it is not ''legal evidence'' - you could testify in court that I had ''told'' you my socks were white, but you could not testify that my socks were white.
  
Rational evidence in the broadest sense may be useful only for private thinking, or thinking in the company of trusted friends.  Scientific, political, or legal processes may (for good reasons) operate with less trust, and impose special and additional standards of admissible evidence.  The [[science|scientific method]] can be viewed as a special standard of admissible evidence protecting a pool of extra-strong beliefs.
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The [[science|scientific method]] can be viewed as a special standard of admissible evidence protecting a pool of extra-strong beliefs.  Conversely, a fact can be rationally guessable without it generating the specially strong evidence which would qualify knowledge of the fact as "scientific".  Just as a police detective may rationally know the identity of the local crime boss without having the special evidence needed to prove it ''in court''.
  
Conversely, a belief can be rationally knowable without generating the sort of specially strong evidence that would qualify it as "scientific", just as a police detective may rationally know the identity of the city's criminal boss without having the special evidence needed to prove it ''in court''.
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==Main post==
 
 
==Main posts==
 
  
 
*[http://lesswrong.com/lw/in/scientific_evidence_legal_evidence_rational/ Scientific Evidence, Legal Evidence, Rational Evidence]
 
*[http://lesswrong.com/lw/in/scientific_evidence_legal_evidence_rational/ Scientific Evidence, Legal Evidence, Rational Evidence]
 
==See also==
 
 
*[[Evidence]]
 
  
 
==Other posts==
 
==Other posts==
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*[http://lesswrong.com/lw/io/is_molecular_nanotechnology_scientific/ Is Molecular Nanotechnology "Scientific"?]
 
*[http://lesswrong.com/lw/io/is_molecular_nanotechnology_scientific/ Is Molecular Nanotechnology "Scientific"?]
 
*[http://lesswrong.com/lw/qa/the_dilemma_science_or_bayes/ The Dilemma: Science or Bayes?] and [http://lesswrong.com/lw/qb/science_doesnt_trust_your_rationality/ Science Doesn't Trust Your Rationality]
 
*[http://lesswrong.com/lw/qa/the_dilemma_science_or_bayes/ The Dilemma: Science or Bayes?] and [http://lesswrong.com/lw/qb/science_doesnt_trust_your_rationality/ Science Doesn't Trust Your Rationality]
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==See also==
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*[[Evidence]], [[Standard of evidence]]
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*[[Bayes' theorem]], [[Conservation of expected evidence]]
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*[[Traditional rationality]], [[Epistemic hygiene]]
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*[[Exploratory engineering]]
  
 
[[Category:Learning]][[Category:Concepts]]
 
[[Category:Learning]][[Category:Concepts]]

Latest revision as of 00:46, 9 June 2013

Rational evidence is the broadest possible sense of evidence, the Bayesian sense. Rational evidence about a hypothesis H is any observation which has a different likelihood depending on whether H holds in reality or not.

Rational evidence is distinguished from narrower forms of evidence, such as scientific evidence or legal evidence. For a belief to be scientific, you should be able to do repeatable experiments to verify the belief. For evidence to be admissible in court, it must e.g. be a personal observation rather than hearsay.

For example, suppose I tell you that the original author of this paragraph wore white socks while writing it. (In fact, I do so tell you.) You now have rational evidence that the author of this paragraph wore white socks, because I'm more likely to tell you this if I am wearing white socks, than if I'm not (Note: This doesn't prove that I am wearing white socks; this is why it is 'evidence'). But it is not scientific knowledge because there is no experiment you can do for yourself to verify whether it is true. And it is not legal evidence - you could testify in court that I had told you my socks were white, but you could not testify that my socks were white.

The scientific method can be viewed as a special standard of admissible evidence protecting a pool of extra-strong beliefs. Conversely, a fact can be rationally guessable without it generating the specially strong evidence which would qualify knowledge of the fact as "scientific". Just as a police detective may rationally know the identity of the local crime boss without having the special evidence needed to prove it in court.

Main post

Other posts

See also