1. A falasafaz! presentation
Arguments
A falasafaz! presentation

2. Which arguments?
Not this
More like this

3. Defining Arguments
An argument is a connected series of statements intended to establish a proposition.
Reasons – and the relations between them – determine whether we should logically accept a particular conclusion.

4. Activity #1
Using the video (click here or the witch): What reasons are offered to logically support the conclusion that ‘she is a witch’?

5. How do you know she’s a witch?
She looks like a witch – she’s dressed like a witch, is wearing a pointy hat, has a pointy nose, and she even has a wart. Therefore, she’s a witch.
Problem: The villagers dressed her as a witch. Not only is her looking like a witch an illusion, but it isn’t one she’s responsible for.

6. How do you know she’s a witch?
She turned the villager into a newt (even though he got better).
Problem: ????

7. How do you know she’s a witch?
You burn witches
You also burn wood
So witches must burn because they’re made of wood
(3) Sir Bedevere’s witch-finding argument:
What do you do with witches? Burn them.
What do you burn apart from witches? Wood.
Why do witches burn? Because they’re made of wood.
How do we tell if she’s made of wood? Build a bridge out of her.
But can’t you also make bridges out of stone? Yes – so building a bridge out of her won’t tell us if she’s made of wood.
Does wood sink or float? It floats.
What also floats in water? Not bread, apples, small rocks, cider, churches, lead, but a duck.
So logically, if she weighs the same as a duck then she’s made of wood, and therefore is a witch (and therefore BURN HER!).
But how do we know she’s made of wood?

8. How do you know she’s a witch?
But! As well as burning, wood also floats.
Make a bridge out of her?
NO.
You can make bridges out of stone or wood, so making a bridge out of her won’t tell you if she’s wood.
Ducks also float. Therefore…

9. How do you know she’s a witch?
If the woman weighs the same as a duck…
Then she’s a witch.

10. Recap on arguments Reasons Inference Assumptions Conclusions
Implications

11. Evaluating arguments? Are the reasons true?
Are the reasons relevant and significant to the conclusion?
Is the inference valid?
Is the conclusion plausible?

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