objective: use the law of detachment and the law of …...2 3 deductive reasoning (monty python)...
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23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1410:17 AM
23 Deductive Reasoning
Objective:
Use the law of detachment and the law of syllogism.
Logic and Monty Python's Quest for the Holy Grail
23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1410:29 AM
witchesweighs as much
as a duck
Write a conditional to describe the above Venn diagram.
If she is a witch, then she weighs as much as a duck!
23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1410:39 AM
If I give you this conditional
AND tell you that someone is a witch, what is the only conclusion you can make?
They weigh as much as a duck!
If she is a witch, then she weighs as much as a duck!
This is called the Law of DetachmentIf a conditional is true and it's hypothesis is true, then the conclusion is true.
Symbolic Form: If p q is a true statement and p is true, then q is true.
23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1410:51 AM
For the given true statements, what can you conclude?
1. If it is made of wood, then it floats on water. My boat is made of wood.
Conclusion:
Using the Law of Detachment, your only conclusion is that my boat floats on water.
2. If M is the midpoint of a segment, then it divides the segment into two congruent segments. M is the midpoint of AB.
Conclusion:
Using the Law of Detachment, your only conclusion is that AM = MB.
23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1410:59 AM
Here are two conditionals that we will assume true:
If she is a witch, then she weighs as much as a duck.If she weighs as much as a duck, then she floats on water.
What conclusion can you make from the above statements?
If she is a witch, then she floats on water!
This is called the LAW OF SYLLOGISM
If p q and q r are true statements, then p r is a true statement.
23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1411:10 AM
For the given statements, what can you conclude?
1. If a number is prime, then it does not have repeated factors. If a number does not have repeated factors, then it is not a perfect square.
Conclusion:
If a number is prime, then it is not a perfect square.
2. If a number is divisible by 10, then it is divisible by 5. If a number ends in 0, then it is divisible by 10.
Conclusion:
If a number ends is 0, then it is divisible by 5.
23 Deductive Reasoning (Monty Python) VIDEO
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September 14, 2010
Sep 1411:17 AM
HOMEWORK
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