Universal Negative -- No S is P.
O.

Particular Negative -- Some S is not P.
As an aid to the remembering of these symbols we may observe that A.and I.are the first two vowels in _affirmo_ and that E.and O.are the vowels in _nego_.
It must be acknowledged that these four kinds of proposition recognised by Formal Logic constitute a very meagre selection from the list of propositions actually used in judgment and reasoning.
Those Logicians who explicitly quantify the predicate obtain, in all, eight forms of proposition according to Quantity and Quality: [Transcriber's Note: The Greek characters used in the original are represented below by the name of the character in square brackets.] U.

Toto-total Affirmative -- All X is all Y.
A.

Toto-partial Affirmative -- All X is some Y.
Y.

Parti-total Affirmative -- Some X is all Y.
I.