Syllogism: Simple explanation, example and etymology of dialectical and scientific syllogism. What is Aristotelian syllogism and how to recognize it.
Syllogism is a type of logical reasoning , always associated with the figure of the great Greek philosopher Aristotle who first conceived this type of reasoning. Syllogism means a consequential discourse that starts from certain premises to arrive at logical conclusions.
Let’s see in detail how it works with some examples and what is the difference between a dialectical and a scientific syllogism.
Syllogism: How it works
The syllogism is made up of three propositions , of which two are the premises and one is the conclusion . The most famous example of an Aristotelian syllogism is probably this:
- Foreword : Every animal is mortal
- Premise : Every man is an animal
- Conclusion : Every man is mortal
But how can we establish that the syllogism, or its conclusion, is valid?
This is possible thanks to the so-called middle term (in our case “animal”) which unites the other two terms (it is contained in the major one – “mortal” – and contains the minor one “man”).
Dialectical syllogism and scientific syllogism
On the other hand, a syllogism could be valid but, at the same time, not true. How is this possible? If my starting premise were: “Every man is immortal,” I could derive a valid syllogism but with false conclusions (“every man is immortal”).
Let’s see two types of syllogism:
- Scientific syllogisms , which for Aristotle are those that start from true premises. At the basis of the sciences (and of every deduction) there are general principles called axioms and definitions that are indemonstrable but evident, which can be grasped only through an act of intuition of our intellect.
- Dialectical syllogisms , whose premises are probable, accepted by most, but not necessarily true. They fall within the scope of discussions and are based on the dialectical procedure and not on the scientific (or demonstrative) one.
