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# Syllogistic Logic

Syllogisms are the original logic, going back to Aristotle. They still find prominence today in the form of Venn and Euler Diagrams.

#### Challenge Quizzes

Which of the following statements is $$\color{red}{\text{not}}$$ consistent with the above diagram?

All Wannts are Tuuus.
Some Tuuus are Triiis.
All Triiis are Forees.

Is the following statement necessarily true?

All Forees are Wannts.

All bookstores sell stationary items.
All convenience stores sell stationary items.

Which of the following conclusions might be true?

$$\text{(1)}$$ All bookstores are convenience stores.
$$\text{(2)}$$ All convenience stores are bookstores.

A friend of Will's is not a friend of Jack's.
A friend of Hannibal's is not a friend of Jack's.

Which of the following conclusions must be true?

$$\text{(1)}$$ Some friend of Will's is a friend of Hannibal's.
$$\text{(2)}$$ Some friend of Hannibal's a friend of Will's.

All Faivvs are Sivkks.
All Faivvs are Sevvens.

Given the above two statements (and the fact at least one Faivv exists), is the following statement true?

No Sivkks are Sevvens.

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