How do two negatives equal a positive?

[Ripley]

No text needed.......hah.

[kiahzero]

1. These are added

Added negatives never equal a positive.

If they were multiplied, then they'd equal a positive.

[apnu]

2. and then there is logic

When doing proofs certain things make a negative and sometimes a negative becomes a double negative that becomes a positive.

Like this Modus Tollens rule that says
if you have P then Q
Then you have ~Q (not Q)
You can deduce ~P

and by that logic...

If ~P then Q
~Q
Therefore ~~P
(and there's another replacement rule that turns ~~P into P called Double Negation)

[DieboldMustDie]

3. "...if it was so, it might be;

and if it were so, it would be; but as it isn't, it ain't. That's logic." ;)

-- Tweedledee

[apnu]

6. yup that's logic for you.

Although logicians make it out to be much more grand sounding, but that's all it is. Oh! that and it's a tool for other sciences and lawyers to abuse.

[Ripley]

11. I don't get it.

Yet.

[tg]

7. The method employed I would gladly explain

While I have it still fresh in my head
If I had but the time and you had but the brain
But so much yet remains to be said.

-- Hunting of the Snark

[Ripley]

8. aaackk.

Mr. Ripley ...bad news.
Ripley's Mom...bad news.

Sorry I'm not a good scientist,,,

[apnu]

10. you're missing one component

"Logically" speaking. You seem to have two premises but no conclusion. In logic, all statements are translated into a variable letter, that's positive. So "Mr. Ripley... bad news." could be shown as "M" and "Ripley's Mom... bad news." could be "R"

So if you negate "M" as "~M" you'd have Mr. Ripley... (does not have) bad news."

But that's just messing around with premises, you don't have a conclusion, like "Therefore, there is bad news." or "I conclude that there is not bad news."

All logic statements must have at least one premise and one conclusion.

[Ripley]

12. God is.

God is not.

[apnu]

15. You can say that as a premise

But "God is not." isn't a conclusion. You're just using the Double Negation translation to turn a positive into a negative. Which is a "legal" move in proof concepts to prove a conclusion, but as you have it, "God is not" isn't the conclusion. You need something in there to help you conclude that "God is not."

A valid argument (which isn't necessarily true or false) could be:

People tell me that God is. (your "god is." statement)
But I haven't found God.
-------
Therefore God is not.

However, not to confuse you, but that's called a False Dichotomy. Saying that there is no evidence for something and then basing a positive or negative conclusion based on lack of evidence is considered a fallacy.

It's really hard to argue God in logic, for or against, without falling into the trap of a fallacy. Most logicians will avoid it if they can.

[Az]

4. So this english teacher is teaching his class about double negatives

He tells them that while a double negative results in a positive statement a double positive does not result in a negative statement.

From the back of the class a student mutters "Yeah, right."

[BigMcLargehuge]

5. HAHAHAHAHAHAHHA!!!!

:)

[mike1963]

9. Okay, turd, you owe me a keyboard!

:D

[Selwynn]

13. That's funny!

[TahitiNut]

14. How don't two negatives not equal a positive?

:shrug:

[apnu]

16. heh

LOL you're statement is amusing... I had to think about it for a while. Nice mind bender there.