dialectical argument and the art of dialectic
Aristotle often contrasts dialectical arguments with demonstrations. The difference, he tells us, is in the character of their premises, not in their logical structure: – whether an argument is a […]
Aristotle often contrasts dialectical arguments with demonstrations. The difference, he tells us, is in the character of their premises, not in their logical structure: – whether an argument is a […]
Aristotle follows his treatment of “arguments in the figures” with a much longer, and much more problematic, discussion of what happens to these figured arguments when we add the qualifications […]
1) There are only three terms in a syllogism (by definition). 2) The middle term is not in the conclusion (by definition). 3) The quantity of a term cannot become […]
Having established which deductions in the figures are possible, Aristotle draws a number of metatheoretical conclusions, including: – No deduction has two negative premises – No deduction has two particular […]
The Deductions in the Figures (“Moods”) see also: http://eidetisch.tumblr.com/post/45789462673/the-figures In Prior Analytics I.4-6, Aristotle shows that the premise combinations given in the following table yield deductions and that all other […]
Disproof: Counterexamples and Terms Aristotle proves invalidity by constructing counterexamples. This is very much in the spirit of modern logical theory: – all that it takes to show that a […]
Methods of Proof: “Perfect” Deductions, Conversion, Reduction Aristotle’s proofs can be divided into two categories, based on a distinction he makes between “perfect” or “complete” (teleios) deductions and “imperfect” or […]
The Figures see also: http://eidetisch.tumblr.com/post/45801450925/the-deductions-in-the-figures-moods | First Figure | Second Figure | Third Figure | | Predicate Subject | Predicate Subject | Predicate Subject | | Premise | a b […]
The Syllogistic Aristotle’s most famous achievement as logician is his theory of inference, traditionally called the syllogistic (though not by Aristotle). That theory is in fact the theory of inferences […]
The “Square of Opposition” In On Interpretation, Aristotle spells out the relationships of contradiction for sentences with universal subjects as follows: | | Affirmation | Denial | | Universal | […]