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Doug, a student in this class, knows how to write programs in JAVA. Everyone who knows how to write programs in JAVA can get a high-paying job. Therefore, someone in this class can get high-paying job.

1 Answer

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Missing Part of Question

Explain which rules of inference are used in the above

Answer:

Universal instantiation, Modus ponens and Existential generalization

Explanation:

Splitting the Statement into two, we have

"Doug knows how to write program is Java"

and

"Doug can get a high paying job"

Represent Doug with x. Then the statements is rewritten as

P(x) = "x knows how to write program is Java"

and

Q(x) = "x can get a high paying job"

In logic, A premise is a statement in an argument that provides reason or support for the conclusion.

So, Statement 1 can be written as

1. P(x) ---- Premise

Then, we have

2. Vx(P(x) --> Q(x)) -- Premise. This mean that P(x) for all values in the domain.

The universal instantiation of (2) leads to

3. P(Doug) --> Q(Doug)

The modus ponens of the above gives

4. Q(Doug)

The existential generalisation from above gives

5. ƎxQ(x)

Which means someone in this class can get a high paying job.

PS:

Universal Instantiation is a valid rule of inference from a truth about each member of a class of individuals to the truth about a particular individual of that class; it is represented by VxP(x).

Existential Generalisation is a valid rule of inference that allows one to move from a specific statement, or one instance, to a quantified generalized statement, or existential proposition.

It is represented as ƎxP(x)

User Jim Ierley
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