2+2 = anything other than 4?

[callmekenneth]

he guys,

i have a question/ challange for you.
me and a friend had an argument about religon, that turned to about logic and finaly math. the result was a bet that any fact could be logicaly disproven.

in order to win this bet i need to prove that 2+2 dose not = 4.

can anyone help me with this? please!

[Rassis]

Funny...I have just seen a similar question in another maths forum. It is perhaps that friend of yours willing to win as well...

[callmekenneth]

i also posted on the mathlinks forum and yahoo anwnsers.

the closest anyone has got is that appromatly 2+2 can = 5.

as 2.4 would be rounded down to 2. so 2.4+2.4 = 4.8 that would be rounded up to 5.

can anyone beat this?

[Dnereb]

Use doubles to store the values of 2 in. (notorious for rounding issues)
add .999999999999999 an subtract it again
add them together...

Sub TwoPlusTwoIsNotFour()

Dim Val1 As Double
Dim Val2 As Double
Dim Cnt As Long
Dim Result As String



Val1 = 2
Val2 = 2

For Cnt = 1 To 1000
    Val1 = Val1 + 0.999999999999999
Next

'subtracting the added valu at once
Val1 = Val1 - 999.999999999999

Result = Format$(Val1 + Val2, "0.000000000000000")

MsgBox "Two plus Two is: " & Result & " and that's a fact!"

End Sub

I want half your gain or a reputation point for this

[capsulecorpjx]

i also posted on the mathlinks forum and yahoo anwnsers.

the closest anyone has got is that appromatly 2+2 can = 5.

as 2.4 would be rounded down to 2. so 2.4+2.4 = 4.8 that would be rounded up to 5.

can anyone beat this?

Good job, you just proved 2.4 + 2.4 = 4.8.

To the original poster, no its not possible.

[Andy_P]

If you read 2+2 from a boolean logic arithmetic sense, the + operator means OR, therefore 2 + 2 = 2.

[bilm_ks]

2+2 = 1 (in Z3) 2+2 = 0 (in Z4)

[kberry79]

In base 3, 2 + 2 = 11. In base 4, 2 + 2 = 10. Bases >=5, 2 + 2 = 4. Bases <=2 the number two does not exist. Base 2 is binary (10 + 10 = 100).

The only way to change simple arithmetic is to change the meaning (definition) of the numbers or the definition of the arithemtic operation.

[namrekka]

In boolean arithmetic + means OR so:
2 + 2 = 2

[Iron Skull]

or you can say..
2 = 1 + 1 Right..
1 = 3/3 Right..
1/3 + 1/3 + 1/3 + 1/3 + 1/3 +1/3 = 2
1/3 = 0.333
So Logical
0.333 + 0.333 + 0.333 + 0.333 + 0.333 + 0.333 = 1,998
So 1 + 1 is not 2

Cant explain it anybetter I think..

[agmorgan]

At least the winner can have a T-Shirt
http://www.thinkgeek.com/tshirts/science/60f5/

[zaza]

or you can say..
2 = 1 + 1 Right..
1 = 3/3 Right..
1/3 + 1/3 + 1/3 + 1/3 + 1/3 +1/3 = 2
1/3 = 0.333 Wrong!
So Logical
0.333 + 0.333 + 0.333 + 0.333 + 0.333 + 0.333 = 1,998
So 1 + 1 is not 2

Cant explain it anybetter I think..

Iron Skull displays his Iron Skull.

[Iron Skull]

Iron Skull displays his Iron Skull.

heh ok what is 1/3 then?

[sevenhalo]

heh ok what is 1/3 then?

[Iron Skull]

heh look what you said

1/3 is equal to 0.3333333 and to 0.3(with stroke through it)
You said it your self.. 1/3 is equal to 0.33

[sevenhalo]

You forgot the ellipse which indicates repeating... Also, that "stroke through it" is the symbol for it.

Let me put it in MTG terms for you. That slash is like a permanant chant on the 3. It doesn't go away, it persists through each turn. You can't ignore it. Also, a white and blue circle of protection are in play, so you are unable to counterspell or dispel the effect.

[jemidiah]

It's fairly simple to prove that 2+2=5. All you have to do is change around the basic axioms of algebra, or the meaning of the number 5 (make 5 mean 4 and 4 mean 5).

The thing is, this would be considered by most people to be 'cheating' by changing the rules of the game. The only way you'll ever prove that 2+2=5 is by changing the rules, and the smallest, most innocent looking change is probably going to be considered the 'best' one. This type of problem is, IMO, stupid simply because there is no answer, and people always get all worked up about nothing.

You can prove anything to be anything by using different rules; the problem lies in using the 'correct' mathematical rules to prove that 2+2=5, and this is plain and simple impossible because mathematicians tend to love working in a closed system without contradictions.


Getting into the original argument, which is a little OT: IMO, you can say any fact can be disproven logically if you refuse to accept absolute truth, that some truths are true whether or not you accept them. This amounts to actually believing that, using the 'correct' rules properly, 2+2 can truly = 5, at least to one person. Also IMO, people who don't accept absolute truth are pretty misguided. I honestly think the only reason they don't is simply so they don't have to play by the rules (in this case the rules of math).

Hope that helps the discussion with your friend some.

[sevenhalo]

You can prove anything to be anything by using different rules

What you're saying is, "You can prove anything to be anything by using anything." Which of course is true and more OT then any point made so far.

[jemidiah]

Did you read the rest of my post? Every single attempt from using Boolean arithmetic to using VB rounding errors changes the rules; the point of my post is that there is no way of doing this correctly, and I expounded upon that.

[sevenhalo]

I did read the entire post, but it all boiled down to the same thing. Having a different set of rules will make anything true. The problem with proving or disproving a scenario is finding order in chaos. Saying that "in chaos, this works" is like dumping a jigsaw puzzle on the table, looking at the picture on the box it came from and declaring that as the truth. All things are possible, but the pieces are what proves or disproves it.

Now I'm following you OT, so I hope that sums it up.

[Iron Skull]

Let me put it in MTG terms for you. That slash is like a permanant chant on the 3. It doesn't go away, it persists through each turn. You can't ignore it. Also, a white and blue circle of protection are in play, so you are unable to counterspell or dispel the effect.

LOL... GREAT!!!

I know that it doesnt end.. but then still its 1,999999999999999999... and not 2..

[Andy_P]

Originally posted by jemidiah
Every single attempt from using Boolean arithmetic to using VB rounding errors changes the rules; the point of my post is that there is no way of doing this correctly, and I expounded upon that.

The point is, the original question did not specify which set of rules should apply, therefore the question of 'can 2+2 = something other than 4' becomes an open one, and the answers involving boolean logic and number bases etc are perfectly valid.

This is all IMO of course.

[zaza]

I know that it doesnt end.. but then still its 1,999999999999999999... and not 2..

No no no. capsulecorpjx has already been told about this one. There is another thread entitled something along the lines of "0.999<>1..." which will explain it all.



Please don't bring up this chestnut again.