question about PHIL
dylanma123
complex_forms_of_deduction.docxComplex Forms Of Deduction
A complex form or pattern of deduction involves a combination of forms or pattern of deduction such as modus ponens, modus tollens, disjunctive syllogism, etc., to arrive at a final conclusion or deduction. Therefore, you must know the four basic forms of deduction to do complex forms of deduction.
Example # 1:
1. If P, then Q.
2.Not Q.
3. P or K.
Final deduction or Conclusion: ?????
In this complex form of deduction, we arrive at the final conclusion or deduction as follows:
1. If P, then Q.
2. Not Q
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3. Not P (from 1 & 2 using Modus Tollens)
4. P or K
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Final Deduction or conclusion: K. (from 3 & 4 using Disjunctive syllogism)
Example # 2:
1. P or K
2. If M, then N.
3. If N, then Not K.
4. M.
Final deduction or conclusion:??????
In this complex form of deduction, we arrive at the final conclusion or deduction as follows. We need to write the correct sequence of steps to make the deductions clear and easy:
1. If M, then N.
2. If N, then Not K.
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3. If M, then Not K. (from 1 & 2 using hypothetical syllogism)
4. M.
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5. Not K (from 3 & 4 using modus ponens)
6. P or K
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Final Deduction or conclusion: P. (from 5 & 6 using disjunctive syllogism)
