In the Proposition: "Man is an animal," the term _man_ is the Subject; the term _an animal_ is the Predicate; and the word _is_, is the Copula. The Copula is always some form of the verb _to be_, in the present tense indicative, in an affirmative Proposition; and the same with the negative particle affixed, in a negative Proposition. The Copula is not always directly expressed by the word _is_ or _is not_, etc., but is instead expressed in some phrase which implies them. For instance, we say "he runs," which implies "he is running." In the same way, it may appear at times as if the Predicate was missing, as in: "God is," by which is meant "God is existing." In some cases, the Proposition is inverted, the Predicate appearing first in order, and the Subject last, as in: "Blessed are the peacemakers;" or "Strong is Truth." In such cases judgment must be used in determining the matter, in accordance with the character and meaning of the terms. An _Affirmative Proposition_ is one in which the Predicate is _affirmed_ to agree with the Subject. A _Negative Proposition_ is one in which the agreement of the Predicate and Subject is _denied_. Examples of both of these classes have been given in this chapter. Another classification of Propositions divides them in three classes, as follows (1) Categorical; (2) Hypothetical; (3) Disjunctive. A _Categorical Proposition_ is one in which the affirmation or denial is made without reservation or qualification, as for instance: "Man is an animal;" "the rose is a flower," etc. The fact asserted may not be _true_, but the statement is made positively as a statement of reality. A _Hypothetical Proposition_ is one in which the affirmation or denial is made to depend upon certain conditions, circumstances or suppositions, as for instance: "If the water is boiling-hot, it will scald;" or "if the powder be damp, it will not explode," etc. Jevons says: "Hypothetical Propositions may generally be recognized by containing the little word 'if;' but it is doubtful whether they really differ much from the ordinary propositions.... We may easily say that 'boiling water will scald,' and 'damp gunpowder will not explode,' thus avoiding the use of the word 'if.'" A _Disjunctive Proposition_ is one "implying or asserting an alternative," and usually containing the conjunction "or," sometimes together with "either," as for instance: "Lightning is sheet or forked;" "Arches are either round or pointed;" "Angles are either obtuse, right angled or acute." Another classification of Propositions divides them in two classes as follows: (1) Universal; (2) Particular.