Deductive vs Inductive Reasoning Objectives Use a Venn

Deductive vs. Inductive Reasoning

Objectives • Use a Venn diagram to determine the validity of an argument. • Complete a pattern with the most likely possible next item. • Explain a general rule or pattern given a word and letter pairing.

Vocabulary • • • Deductive reasoning Inductive reasoning Venn diagram Syllogism Valid/invalid argument

• Reasoning: the drawing of inferences or conclusions from known or assumed facts • Deductive reasoning: the application of a general statement to a specific instance • Inductive reasoning: the application of specific instances to form a general conclusion

Classify the argument as deductive or inductive: 1. I ate a chili dog at Joe’s and got indigestion. 2. I ate a chili dog at Ruby’s and got indigestion. Therefore, chili dogs give me indigestion.

Classify the argument as deductive or inductive: 1. All spicy foods give me indigestion. 2. Chili dogs are spicy food. Therefore, chili dogs give me indigestion.

• Syllogism: an argument composed of two statements or premises followed by a conclusion • Valid: an argument if valid if the conclusion of the argument is guaranteed to follow from the premises • Invalid: an argument is invalid if there is at least one instance where the conclusion does not follow from the premises

Draw a Venn diagram to determine if the argument is valid or invalid: 1. No one who can afford health insurance is unemployed. 2. All politicians can afford health insurance. Therefore, no politician is unemployed.

Draw a Venn diagram to determine if the argument is valid or invalid: 1. All homeless people are unemployed. 2. Roseanne is not a homeless person. Therefore, Roseanne is not unemployed.

Draw a Venn diagram to determine if the argument is valid or invalid: 1. All doctors are men. 2. My mother is a doctor. Therefore, my mother is a man.