Semantics I acknowledgements

SEMANTICS
Page Compound propositions can be divided into two parts Propositions which have relation of dependence, one with another. Because of their relation of independent this sort is called Implicative Propositions.
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Proposition whose parts (categorical propositions) are joined by conjunction and.
There are three kinds of implicative propositions they are,
conditional, Disjunctive, and Conjunctive Proposition. Conditional proposition is two propositions which are joined by connectives If, then.
For example, If rainfalls, then the street will be wet. The first proposition is called he antecedent, the second is the consequent.
The relationship between those two propositions is seen through their truth condition. If the antecedent is true, then the consequent must follow. Both parts of the proposition maybe false but the condition can be true. For example ; If cotton is heavier than iron, then its gravitational pull
will be stronger than the iron.
Logicians made the symbol for conditional proposition as if, then. So instead of saying ; if p, then q, we symbolize it asp q
Since the relation of one proposition with another is embedded in their truth condition, it is necessary to setup Truth Tables a proposed by the logicians. Thus the truth tables below indicate what is the truth value of

SEMANTICS
Page the compound sentence in relation to the truth value of the simple sentence from which it is formed.
P
q p
q t
t t
t ff ft t
f ft the first line shows that, if both p and q are true, p q is true. The second line shows that, if pis true, q is true, then p q
is false. The third shows that, if pis false, then p q is true. The last shows that, if both p and q are false, then p q is true.
More examples about this propositional calculus will be given in chapter four.
Disjunctive Proposition is two propositions which are joined by the conjunction or, as examples, let’s look at the prepositional below He is a criminal or he is a sailor.
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Mary is intelligent or she is aggressive..
The first disjunctive tells us that both parts maybe true simultaneously,
therefore it is called weak. In Latin, this proposition is also signed by the word ; vel, Means either and possibly both, is in the insurance policy which is written ; In the event of accident or illness all premiums are cancelled (see also Sullivan : 105.)

SEMANTICS
Page Thus the truth tables of disjunctive proposition an be charted as follows :
P
q p
V
q t
t t
t ff ft t
f f
f
The first line indicates that, if both p and q are true, then p V q (read p or q) is true. The second line tells us that, if pis true and q is false, then p V q or the compound propositions are true. Then if both p and q are false, the compound propositions are true.
The third kind of implicative proposition is Conjunctive
Proposition, that is, two propositions which are joined by and. For example
:
She cannot eat and he is not thin.
Birds cannot fly and whisper.
The conjunctive proposition has also strong and weak form. The strong conjunction shows that part of it, not both, must be false, as seen in the first example. Whereas the weak conjunction, both parts must be false,
like in the second example

SEMANTICS
Page From both examples, we see that they are in the negative for. So conjunctive proposition is always in his form.
The propositional calculus (the relationship between the parts of the proposition) in conjunctive form can be charted in the following of which the symbol is given for conjunctive (p & q is read p and q).
P
q p
&
q t
t t
t ff ft ff ff from the truth tables we can state that the conjunctive proposition is true only when both parts are true (if pis true, q is true, then p & q is true, like in this proposition ; He is not clever and intelligent.
Besides the negative forms, the positive forms of conjunctive propositions are found. Let’s see some examples Sea is deep and sky is blue.
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Dogs are animals and apples tree are plants and stones are solid and humans are mortal.
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She is pretty, kind and skillful.
From the examples it is seen that the conjunction and, function as joining one part to the other parts of categories.

SEMANTICS
Page If in the previous propositions, the relationship between them can be shown in truth tables, but here it seems that their relation cannot be shown. The reason is that, how do we make symbol such p, q, or the others to the sentence which I long Or if our sentence is like this : The book is thin and the pencil is long and the penis new and the paper is white,….,
etc”. It is very complicated indeed.

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