Tool to test or create syllogisms. A syllogism is a sequence of affirmations allowing to make a deduction. All men are mortal. Socrates is a man. Therefore Socrates is mortal.
Syllogisms - dCode
Tag(s) : Algorithm
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A syllogism is, in its simplest form, a set of 2 statements from which a conclusion is deduced. The two affirmations are named the premises: the first premise (major) and the second premise (minor). A syllogism is generally written in 3 lines, the third is deduced from the first two.
Example: All men are mortal (affirmation 1: major premise)
Socrates is a man (affirmation 2: minor premise)
So, Socrates is mortal. (conclusion)
There are an infinity of syllogisms, but structurally there are only 24 types of syllogisms which can have a logical conclusion.
The conclusion is a purely logical conclusion. If at least one of the 2 assertions / premises is false, then it is possible to deduce things that are completely false, although perfectly logical. Similarly, it is possible to deduce something right from false or incomplete premises.
Example: dCode is a website. (true premise)
All websites are great. (sic, wrong premise)
So, dCode is great! (true conclusion)
For a syllogism to be valid, it must consist of two premises. A premise is itself made up of a quantity (All, None, etc.), a subject, a verb (is / is not) and a predicate (a subject attribute). The two premises must also have a pivot subject or predicate, ie it must be part of the 2 premises.
Example: No A are B. All C are A. => No C are B.
dCode can not handle plurals or variant spellings. Make sure to write exactly the same words for the pivot element (ideally a singular script).
There is only one logical conclusion for any given pair of premises. Indicate the 2 premises on dCode, and compare the conclusion to check validity.
The syllogisms are used for logical reasoning and consequently, they are widely used for recruitment tests, entrance exams, for example in law, medicine, etc.
A paralogism is an invalid syllogism, which leads to an absurd conclusion from premises that seem correct but are actually false. The best known is the paradox of cheese with holes:
Example: The more cheese there is, the more holes there are. But the more holes there are, the less cheese there is. So the more cheese, the less cheese!
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