Deductive Argument
Raju Thapaliya
HUMN210-H6WW (WI13)
Mariam Abbott
Franklin University
11thApril, 2013

Example no.1:
1) If p, then q.
2) p.
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3) Thus, q.
This form is called modus ponens ("the mode of putting": put p, get q ). Taking p to stand for "I study", and q to stand for "I get good grades".
1) If I study, then I get good grades.
2) I study.
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3) Thus, I get good grades.

Example no.2
1) If p, then q.
2) Not q.
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3) Thus, not p.
This form is called Modus tollens (" the mode of taking": take q, take p)."Not-q" simply stands for the denial of q, that is for the sentence "it is not the case that q."The same is true for "not-p."
1) If I study, then I get good grades.
2) It is not the case that I get good grades.
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3) Thus, it is not the case that I study.
Example no.3
1) If p, then q.
2) If q then r.
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3) Therefore, if p then r.
This form is called Hypothetical syllogism
For instance
1) If I study, then I get good grades.
2) If I get the good grades, then I pass the course.
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3) Therefore, If I study then l pass the course.
Example no.4
1) p or q.
2) Not- p.
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3) Therefore, q.
This form is called Disjunctive syllogism. For instance
1) Either I study or I get good grades.
2) I can't study.
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3) Therefore, I get good grades.

Example no.5
1) p or q.
2) If p, then r.
3) If q, then s.
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4) Therefore, r or s.
This form is called Dilemma. For instance
1) Either I study or I get good grades .
2) If I study, then I pass the course .
3) If I study, then I learned the material.
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4) Therefore, I pass the course or I learned the material.