Chapter Eight: “Say What You Mean and Mean What You Say” (The Art About Statements)
A statement is speech which signifies something true or false. A statement is not the only
kind of sentence, but it is the only kind of sentence which signifies the true or the false. Compare the
following three sentences: Go to the store. I went to the store. Should I go to the store? On the face
of it they may seem very much alike. But one is a statement and the others are not. When a sentence
signifies a command or a question, it does not signify that something is or is not so. On the other
hand, a statement signifies that something is or is not so.
When a statement signifies that what is, is so (for example, the number three is odd); or when
a statement signifies that what is not, is not so (for example, three is not even), then this statement is
true. On the other hand, when a statement signifies that what is, is not so (for example, five is not
greater than four); or when a statement signifies that what is not, is so (for example, four is greater
than five), then this statement is false. So truth and falsity depend upon whether a statement signifies
something which agrees with reality. Truth is the conformance of the mind with reality.
Often we do not know or cannot even determine whether a given statement is true or false.
Nevertheless, we do know that it cannot be both true and false at the same time. It has to be one or
the other. In certain cases, a statement is neither true or false. For example, a statement about a future
event which is not necessary, like: I will get an A on my next test. Although this statement is not true
or false yet, it will at some time be true or false, and so it still falls under the definition of statement
given above.
The Genera (Kinds) of Statements
Some statements are simple, others are compound. In a simple statement one thing is affirmed
or denied of another. For example, “man is an animal” or “man is not a stone.” A compound statement
is composed of simple statements. Three kinds of compound statements which are particularly
important in Logic are the and statement, the if–then statement, and the either-or statement. An
example of the and statement is “I ran to the store and I bought an ice cream.” An example of the if–
then statement is “If a man is a saint, then he will go to heaven.” An example of the either-or statement
is “A number is either odd or even.” Notice that the simple and the compound statements are called
“statements” equivocally by reason, rather than univocally. Since a statement is speech signifying
the true and the false, but true and false mean something different in the simple statement than in the
compound statements as we shall see later. Since the compound statement is composed of simple
statements, we will examine simple statements first.
The Composing Parts of a Simple Statement
Whenever we want to understand something, it is generally useful to break it down into its
parts. This is a universal rule applicable to every branch of knowledge. What are the parts of a
statement then? If we treat a statement as an integral whole, then we can divide a simple statement
into either two or three parts.
One way to divide a simple statement is to divide it into two parts, namely, a noun and a verb.
Both a noun and a verb are kinds of words or names (speech having no parts which signify by
themselves), but the noun signifies without any reference to time, while a verb signifies with some
reference to time. For example, in the statement man walks, man is a word which signifies something,
but without time. But the word walks signifies with time, since it indicates something happening in
the present. Because a verb signifies with time it can have several tenses such as walked, signifying
the past, or will walk, signifying the future. A verb is also a sign of something said of a subject. Thus,
a verb always implies some subject (in this example, walks is a sign of a particular kind of motion
said of man). Therefore, we can define a noun as a word which signifies without time, and we can
define a verb as a word which signifies with time, and which is a sign of something said of a subject.
We can also divide a simple statement into three parts by further dividing the verb into a
copula and a predicate. In these cases, the verb is expressed as a combination of the verb “to be” and
a predicate. For example: man is walking, or man is animal. In these examples, “man” is the subject,
“is” is the copula, and “walking” and “animal” are predicates.
The Species of a Simple Statement
A simple statement can also be treated as a universal whole which can be divided into different
kinds or species. If we consider the quality of a statement, then we can divide statement into
affirmative and negative statements. An example of an affirmative statement is “trees are plants.” An
example of a negative statement is “trees are not plants.” Affirmative and negative statements are
different species of statements because they are different ways of being a statement.
If we consider not the quality, but rather the quantity of a statement, we can divide statement
