1+1=3....or is it 2+2=5....Well: either way, i don't understand it

Factual Questions
1

Yeah yeah yeah…i know that there was a mailbag article on this subject a while ago, but I do remember reading something to the effect of 1+1=3 in large numbers. It did not seem like a joke as it did include the name of some obscure mathematical theorum. (Of course, I can’t rember the name of the theorum, so it mighta been “YouSchmuckICantBeliveYouFellForIt’s theorum of large and non-existant numbers”)

Well, at any rate, I asked this question that I now pose to you to my math teacher who promptly gave me the “you’re crazy” look that i really should be used to by now, and then went back to the curriculum.

Please help, as I’d really like to satiate my curiousity (and prove my math teacher wrong).

Oh yeah…please include cites if possible, cause if I just print out this thread, she’s liable to say “Who are these morons, and why are you listening to them and not me?”

2

AFAIK, it’s just a joke, often going under the name “Fermat’s Second to Last Theorem”.

Usually, it refers to rounding error. For example,
2.3 may be rounded down to 2
2.4 likewise

2.3 + 2.4 = 4.7

4.7 may be rounded up to 5.
Therefore, if done on a caculator set to display only one digit, but storing others in its memory, 2+2 =5 for very large values of 2.

3

That’s what the mathematicians say, anyway. I’d always heard it as a commentary on the habits of some physicists: If, for instance, you have a formula from quantum mechanics, and you want to see what it means for classical stuff (above the quantum level), then you set hbar to zero in the formula, and see what it looks like. You might then say something like “For small values of hbar, this reproduces the classical result”. Similarly, you might classicalize a relativity formula: “For large values of c…”. Of course, it isn’t really meaningful to talk about “small values of hbar” or “large values of c”, since they’re both so fundamental: You might as well talk about large values of two.

I’ve always remembered it as attributed not to Fermat, but to Dirac, which seems reasonable. What do you expect from a guy who builds a theory of gravity out of the fact that one is approximately equal to two thousand?

4

This isn’t really mathematical but 1+1=3 does apply in other fields. One color (blue) + one other color (yellow) = a third color (green). It also can apply to philosophy, chemistry, physics, or anywhere one idea/object added to another independent idea/object can make a third idea/object.

5

Surely this is a case of 1+2=3 (i.e. one colour added to a second colour gives a third colour)

:slight_smile:

pG

6

I read something like that, or was it exactly like that? It was in the novel 1984. Part of how they brain wash people.

7

I think this is what people refer to as something being greater than the sum of it’s parts - a phenomenon which can only occur where quantitative/qualitative measurements are subjective, for example:

White bread+Mature Cheddar+Sliced Tomato+Branston Pickle

results in a surprisingly good sandwich - it tastes better than you would imagine*, so it can rightly be described as being greater than the sum of it’s parts, but only because there isn’t an objective way to measure how nice something tastes.

*It really does - try it.

8

In some early FORTRAN (early computer programming language) compilers, I believe, they actually let you reassign the values of numeric constants. So you could say, for example:

LET 1=2
LET 2=3
LET A=1+2
PRINT (A)

Ouput would be: 5

Forgive me if the syntax is incorrect, I haven’t touched FORTRAN in 12 years.

9

In 1984 by George Orwell, the main character says that freedom is the freedom being able to say that 2+2=4. When Big Brother brainwashes the main character they make him believe that 2+2 can equal 5 or whatever Big Brother wants it to be.

10

The Staff Report (it was called “Mailbag” back in those balmy days) is: Does 2 = 2 = 5 for very large values of 2?

It’s written with such insight and pith, such style, such grace, that this should be the last word on the topic. And the author should get a raise.

There was some discussion in the forum called “Comments on Staff Reports” as well: 2 + 2 = 5

[Edited by C K Dexter Haven on 05-31-2001 at 11:47 AM]

11

[begin Patrick Stewart impression]
There are FOUR lights!
[end Patrick Stewart impression]

12

I wonder who might have written such a masterpiece…Wait, was it Dex?? :smiley:

Seriously, I did think it was a good article.

13

frogstein

I took FORTRAN in college. I think I know what you are talking about. FORTRAN passes arguements to parameters by reference even if the arguement is a literal “constant”. So if SUBRTN adds one to its parameter and you CALL SUBRTN(10) then add 10 to a variable, the variable will increase by 11. I ran into a FORTRAN programmer a few years ago and told him about that. He did not believe me, so we ran a test using 1 instead of 10. At first it looked like I was wrong, but we discovered that was because on a PC, there is an instruction to increment by 1 and the compiler used that instead. When we tried again with 10, the value of 10 became 11.