Page 136 - Intelligent Communication Systems
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CHAPTER 10 / BASIC TECHNOLOGY OF THE INTELLIGENT COMMUNICATION SYSTEM I I §
performed as follows:
According to prepositional logic, (p A q) -» r is not valid but is satisfactory.
So this problem cannot be solved by prepositional logic. Instead, it should be
solved as follows:
"A human dies" is notated
"Ted is a human" is notated
By assigning 'Ted" to jc in statement (1), we obtain Die(Ted).
Human and Die are called predicates. Ted and x are called parameters. In addi-
tion to predicate symbols such as Human, Die, and Ted, predicate logic introduces
a universal quantifier (V) and an existential quantifier (3). Using these quantifiers,
statement (1) can be notated as:
This means that if x is a human, then x dies for all x.
An existential quantifier is used as follows:
This means that if x is a flower, then there is a red flower x.
