second
vowel of _aff_Irmo).

Some S is not P is called the PARTICULAR NEGATIVE, symbol O (the
second vowel of _neg_O).

The distinction between Universal and Particular is called a
distinction in QUANTITY; between Affirmative and Negative, a
distinction in QUALITY. A and E, I and O, are of the same quantity,
but of different quality: A and I, E and O, same in quality, different
in quantity.

In this symbolism, no provision is made for expressing degrees of
particular quantity. _Some_ stands for any number short of all: it may
be one, few, most, or all but one. The debates in which Aristotle's
pupils were interested turned mainly on the proof or disproof of
general propositions; if only a proposition could be shown to be not
universal, it did not matter how far or how little short it came. In
the Logic of Probability, the degree becomes of importance.

Distinguish, in this Analysis, to avoid subsequent confusion, between
the Subject and the Subject Term, the Predicate and the Predicate
Term. The Subject is the Subject Term quantified: in A and E,[1] "All
S"; in I and O, "Some S". The Predicate is the Predicate Term with the
Copula, positive or negative: in A and I, "is P"; in E and O, "is not
P".

It is important also, in the interest of exactness, to note that S and
P, with one exception, represent general names. They are symbols
for classes. P is so always: S also except when the Subject is an
individual object. In the machinery of the Syllogism, predications
about a Singular term are treated as Universal Affirmatives. "Socrates
is a wise man" is of the form All S is P.

S and P being general names, the signification of the symbol "is" is
not the same as the "is" of common speech, whether the substantive
verb or the verb of incomplete predication. In the syllogistic form,
"is" means _is contained in_, "is not," _is not contained in_.

The relations between the terms in the four forms are represented by
simple diagrams known as Euler's circles.

[Illustration:

1 concentric circles of P and S - S in centre A
2 S and P in the same circle A
3 S and P each in a circle, overlapping circle. I & O
4 S in one circle and P in another circle. E
5 concentric circles of S and P - P in centre I?
]

Diagram 5 is a purely artificial form, having no representative in
common speech. In the affirmations of common speech, P is always a
term of greater e