Aristotle is considered the father of the syllogism.
A syllogism is an argument made up of three propositions; Of them, the last is the one that is always deduced from the previous ones. The word derives from the Latin concept syllogĭsmus which, in turn, finds its origin in a Greek word.
It must be emphasized that the father of the syllogism is the great Greek thinker and philosopher Aristotle . Thus, he was the first to use this term, starting or establishing what is known as Aristotelian judgments . Specifically, under that name there is a series of terms that come together and give rise to the so-called logic .
More precisely, according to said author, these terms are nothing more than the union of a subject and a predicate . All of this can be contemplated and studied through some of his most important works, among which are, for example, "First Analytics" or "The Organon", which is a compendium of a series of his best works.
Syllogisms and deductive reasoning
It can be considered as a form of deductive reasoning , where two of the propositions are premises and the remaining one functions as a conclusion . The syllogism is an argument in which, based on an antecedent that compares two concepts with a third, it allows us to infer or deduce a consequent.
In other words, it can be said that the syllogism model is composed of three propositions that include a middle term (which is common to the two premises and is discarded in the conclusion) and two extremes. One of the most common examples is the following:
“All human beings are mortal”
“Aristotle is a human being”
“Therefore, Aristotle is mortal.”
The syllogism is a form of deductive reasoning.
False conclusions
It must be taken into account that a syllogism does not always drive true conclusions, regardless of whether it follows a valid form of reasoning . For example:
“All dogs were puppies.”
“Snoopy is a dog”
“Therefore, Snoopy was a puppy.”
Although the syllogism is valid from a logical point of view, the conclusion is false, since Snoopy is a fictional dog and was never a puppy.
It should be noted that syllogisms assume that, from two negative premises, a conclusion can never be obtained. On the other hand, a negative conclusion cannot be obtained from two affirmative premises.
Types of syllogism
The types of syllogism can be classified into four different figures with three terms, which total 256 types of syllogism: of them, only 19 are legitimate.
Among the different types of syllogisms that exist, we can fundamentally highlight three. The first of them is the so-called compound syllogism , which is characterized by the fact that the major premise is a compound proposition and because the minor premise affirms or denies a part of the previous one.
The second type is known as a conditional syllogism . As its name indicates, it states that the major premise is a conditional class proposition and the minor premise is categorical. In the same way, it must be emphasized that there is an antecedent and then a consequent.
The third type of syllogism is the so-called disjunctive . In this specific case, the major premise is disjunctive and the minor premise affirms or denies one of the proposed alternatives. An example would be the following: Either two is an even number or it is an odd number. Two is an even number, therefore it is not odd.