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Basic logic

Syllogism

is basic form of deductive argument, e.g.:

  1. Rational animals are mortal. - major proposition
  2. Socrates is a rational animal. - minor proposition
  3. Therefore Socrates is mortal. - conclusion

Syllogism connects the subject (Socrates) and predicate terms (mortal) of its conclusion through its middle term (rational animal) in its two propositions. The first of which states a general principle and the second brings a particular case under that principle. The conclusion then demonstrates the result of applying the general principle to the particular case.

Subject - the term in a proposition about which something is said in the predicate

Predicate - term that says something about the subject

If you are a programmer you might find this code useful.

Logical expressions

Term (understanding): the subject or predicate of a proposition, expressing a concept

Proposition (judging): declarative sentence, affirmative or negative

Argument (reasoning): a proof that a certain proposition is true by showing that it follows (logically and necessarily) from other propositions being true

Necessary - what cannot be otherwise

Sources