Laws of Logic

Draw a valid conclusion and state the Law used:

 $\sim j\rightarrow\sim m$  

 $\sim j$  

• m, Disjunctive Inference

• ~m, Disjunctive Inference

• ~m, Law of Detachment 
  

• m, Law of Detachment 

If I comb my hair, then I won't have tangles.

I have tangles.

Therefore, I didn't comb my hair.

Which law is being demonstrated?

• Law of Detachment

• Law of Syllogism

• Law of Contrapositive

• No law

If my team wins the game, then they will be the champions.

My team is the champion.

Therefore, my team won the game.

Which law is being demonstrated?

• Law of Detachment

• Law of Syllogism

• Law of Contrapositive

• No law

If you need help, then you stay after class.

If you stay after class, then you ask questions.

What is the logical conclusion?

• Therefore, if you stay after class, then you need help.

• Therefore, if you ask questions, then you need help.

• Therefore, if you need help, then you ask questions.

• There is no logical conclusion.

If you go to the mall, then you will spend money.

You didn't spend any money today.

What is the logical conclusion?

• Therefore, you didn't go to the mall.

• Therefore, you don't have any money.

• Therefore, you went to the mall.

• There is no logical conclusion.

Tags

CCSS.RL.11-12.1

CCSS.RL.8.1

CCSS.RL.9-10.1

CCSS.RI.8.1

CCSS.RI.8.8

If you don't feel well, then you stay home.

You feel well.

What is the logical conclusion?

• Therefore, you stay home.

• Therefore, you don't stay home.

• Therefore, you don't feel well.

• There is no logical conclusion.

Tags

CCSS.RL.11-12.1

CCSS.RL.8.1

CCSS.RL.9-10.1

CCSS.RI.8.1

CCSS.RI.8.8

How do you feel about the Laws of Logic now?

• Great! I am ready to take my quiz!

• Ok. I need to study my notes a bit more before I quiz.

• Not good. I need to practice more and maybe even come to Office Hours. But I will take the quiz before next class.

Use the law of syllogism to draw a conclusion from the two given statements:
Statement 1: If you exercise regularly, then you have a healthy body
Statement 2: If you have a healthy body, then you have more energy

• You have more energy
• If you exercise regularly, then you have more energy
• You have a healthy body
• If you do not have a healthy body, then you do not exercise regularly

p→q
q→r
∴p→r
Which law is modeled?

• Law of Syllogism
• Law of Detachment
• Law of Contrapositive
• Law of Shannon

Draw a conclusion from the statement.
If Jack goes to school, then it is Monday.
Jack doesn't go to school.

• Jack skipped school.
• It isn't Monday.
• It's Saturday.
• Invalid

Tags

CCSS.RL.11-12.1

CCSS.RL.8.1

CCSS.RL.9-10.1

CCSS.RI.11-12.2

CCSS.RI.9-10.1