Edwina, List: ET: 2] If it rains, my car will get wet. My car is wet: Therefore, it rained.
ET: The premises are valid. But the conclusion is invalid - I left the sprinkler on. Admittedly nitpicking here, but *premisses *are not "valid," they are either true or false; only *arguments *are valid or invalid. Also, in this case the argument is *deductively *invalid, but *retroductively* valid--i.e., the hypothesis that it rained is a *plausible *explanation of the surprising fact that my car is wet, given my knowledge of the rule that a wet car would be an outcome of it raining. Regards, Jon Alan Schmidt - Olathe, Kansas, USA Professional Engineer, Amateur Philosopher, Lutheran Layman www.LinkedIn.com/in/JonAlanSchmidt - twitter.com/JonAlanSchmidt On Thu, Oct 5, 2017 at 2:24 PM, Edwina Taborsky <[email protected]> wrote: > Helmut, list - but, can't an inference be illogical in its format? > > For example: > > 1] All cats are animals/ All dogs are animals: Therefore, all cats are > dogs. > > The premises of the above syllogism are valid; but, the reasoning or > conclusion is invalid. [Undistributed middle]. > > 2] If it rains, my car will get wet. My car is wet: Therefore, it rained. > > The premises are valid. But the conclusion is invalid - I left the > sprinkler on. > > Your outline of the three methods of reasoning is a different topic than a > discussion on ''inference' or 'conclusions'. > > Edwina >
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