A Quick Tourof Logos презентация

things that make sense. You can think of it in that way if you like.
“It's pretty sunny today, so you should wear sunscreen.”

said before, you hack.”

Well, yes. But that's how an argument looks in standard
form! You can break down any argument into this form;
that makes it easier to think about.

If it's sunny today, you should wear sunscreen.

It is sunny today.
___________________________________________
Therefore, you should wear sunscreen.

(Premises always come first, and the conclusion always comes last.)

is fuzzy.
2. It also has seeds.
3. If a fruit is fuzzy, it's either a kiwi or a peach.
4. Peaches have a pit; they don't have seeds.
5. So the fruit can't be a peach.
6. So the fruit must be a kiwi.

Which of the above sentences is a conclusion?

is fuzzy.
2. It also has seeds.
3. If a fruit is fuzzy, it's either a kiwi or a peach.
4. Peaches have a pit; they don't have seeds.
5. So the fruit can't be a peach.
6. So the fruit must be a kiwi.

Good logic lets us cobble together lots of
different pieces of information, and tell from
them what's probably or definitely true.

because the conclusion followed from the premises. We'll see what this means in a moment.


Why don't we look at a bad argument?

and lived.

Therefore, if I jump off this cliff, I will definitely be fine.

“Come on.
What could
possibly go
wrong?”

and lived.

Therefore, if I jump off this cliff, I will definitely be fine.

This argument is weak. Although the premise is true,
it's easy to think of ways (very painful ways) that the
conclusion could be false. The easiest way to spot bad
logic is to do just that: try to think of another way out.

(Philosophers call these counterexamples).

arguments.
1. Deductive reasoning:
All interns can breathe fire. So Philip can breathe fire.

Is there a piece of the puzzle missing?

arguments.
1. Deductive reasoning:
All interns can breathe fire. Philip is an intern. So Philip can breathe fire.

Sometimes you may encounter “hidden” statements
and ideas, which the writer sneaks in but doesn't
say outright.

arguments.
1. Deductive reasoning:
All interns can breathe fire. Philip is an intern. So Philip can breathe fire.

Are the premises true?
If so, then the conclusion's
100% guaranteed true.
No getting around it!

arguments.
2. Inductive reasoning:
I touched a stove and it burned me. I did this
fifty times, and the same thing happened. So the
next time I touch the stove, it will burn me.

Are the premises true?
If so, then the conclusion's
probably true. There might
still be exceptions.

to make strong logical arguments will become more and more important later on in high school and college.

Pathos and ethos are still valuable! But your audience will be a lot better at questioning them. Logos is handy because, if you use it well, it can't really be disproved.

to spot weak logic.






Next time you watch TV or go online (with your parents' permission, of course), try to keep track of how many different arguments are being pitched to you by ads. How much info is given to you? How much is left out?

of four. Each group will receive an example
of a poor argument (these may be either inductive or deductive).

With your group, you will have 5 minutes to try to come up with
one counterexample - one way in which the argument
could be wrong, even if the premises are definitely true.
Poke it full of holes!
Also, choose a group representative to tell us your reasoning.

(It's OK to imagine unlikely or weird explanations;
don't be afraid to think outside the box.
Oddly enough, logic has very little to do with facts.)

and I ended up with an A. Tiredness must make me smart!”

COUNTER: What if you got an A because you actually studied?
Or maybe the test was going to be easy for you all along?

ARGUMENT: “If I play with Dad's power tools, he'll yell at me.
But Dad is yelling at me for something. So I guess I must have
played with the power tools.”

COUNTER: What if he's yelling at you for a different reason:
scratching the car, or hammer-throwing the cat onto the roof?