middleterm

It is essential that there should be three, and no more than three, terms, namely, the subject and predicate of the conclusion, and another called the middleterm, which must be found in both premisses, since it is by means of it that the other two terms are to be connected together.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

The most common case is that in which the middleterm is the subject of the major premiss and the predicate of the minor.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

In the fourth figure the middleterm is the subject of the minor premiss and the predicate of the major.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

When the middleterm is the predicate in both premisses, the syllogism belongs to the second figure; when it is the subject in both, to the third.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

As there can be but three terms, the major and minor terms must each be found in one, and only one, of the premisses, together with the middleterm which is in them both.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

This fallacy might also be classed under ambiguous middleterm; _something_, in the one premise, meaning some substance, in the other merely some object of thought, whether substance or attribute.

A System Of Logic, Ratiocinative And Inductive John Stuart Mill 1839

Syllogisms are divided by some logicians into three _figures_, by others into four, according to the position of the middleterm, which may either be the subject in both premisses, the predicate in both, or the subject in one and the predicate in the other.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

A is the minor term, C the major, B the middleterm.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839

The premiss which contains the middleterm and the major term is called the major premiss; that which contains the middle term and the minor term is called the minor premiss.

A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2) John Stuart Mill 1839