Logical & Critical Thinking

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Syllogistic Logic

Syllogistic Logic is a form of logic where conclusions are inferred from two premises. This is easier to understand with examples. I will have to note that this type of logic is rather narrow in scope and archaic. It can form logical arguments but other forms of more modern logic often supersede this. Still it is good to have a familiarity with it.

Syllogistic Examples

Dog Syllogism

Premise: All dogs are carnivorous

Premise: Pugs are dogs

Conclusion: Therefore all pugs are carnivorous

Fish Syllogism

Premise: Fish need water to breathe

Premise: Fish use gills for breathing

Conclusion: Gills use water for breathing

Helpful Syllogistic Links

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3 Responses to Syllogistic Logic

  1. djhmoore says:

    Readers might find this link useful. It is an interactive online Syllogism solver at http://thefirstscience.org/syllogistic-machine/  Good for exploring fallacies, figures, terms, and modes of syllogisms.

  2. Aristotle says:

    Can you demonstrate that the second argument is valid?