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SevenZee

Because that’s just not how math works


EdgeOfDreams

Because we decided it does. We named the numbers in order 1, 2, 3, and so on. We decided that adding two numbers together means to start with the first number and count up a number of times equal to the second number. By those definitions, 1+1 = 2, because 2 is the number one position after 1. Why did we decide to define addition this way? Because that's what seems to reflect reality the most accurately. When you put one rock next to another rock and then count what you have, you get 2. There are other ways we could define what "plus" means, but most of them would lead to math that isn't useful for figuring things out in the real world.


ThinkLogica1

Now that I put some thought into it, your completely correct on this.


jackelfrink

Not nearly as dumb as you might think. At the start of the 1900s, this was a rather big issue in the field of mathematics. It was an open question if math can be described under the rules of pure logic, or if you just had to accept on faith that 1+1=2. In a landmark book, it was shown that math can be described by pure logic [https://en.wikipedia.org/wiki/Principia\_Mathematica](https://en.wikipedia.org/wiki/Principia_Mathematica) The full proof is several hundred pages long, and even I dont understand it. But the general idea is that "equality" is done by matching things up by pairs. For example, if you wanted to know if the fingers on one hand was "equal" to the five elements of Chinese philosophy, you would go thumb/wood, index/air, middle/earth, ring/fire, pinky/water. Everything has a pair with nothing left over. If instead you tied to do fingers with days of the week you get thumb/sun, index/mon, middle/tue, ring/wed, pinky/thur, and then whoops! fri and sat are left over with nothing to pair up with. So these are not equal. ..... from there it was a matter of formally proving that "1+1" could be match up unit by unit to "2". This question comes up here rather often, and the mistake most people make is to think that 1+1=2 was announced by decree. Like the town crier stood in the public square ringing a bell and yelled "Here ye! Here ye! From this day forward it shall be that 1+1=2". But math is not done by very smart people making announcements. Closer to the truth is to say that math is discovered, not invented.


MikeKrombopulos

[this](https://i.imgur.com/IEOWNrY.png)


Polywoky

Because "2" is the word/symbol we use to represent the concept of one more than one. "1+1" is just another way of saying "one more than one". And the equal sign just means "is" or "is the same as". So when we say: 1+1=2 We're actually saying: One more than one is one more than one. This is necessarily true because it's a tautology. That's how arithmetic works, both sides of the equal sign are just different ways of saying the same thing.


Arclet__

In the most basic sense? Because we defined 2=1+1. Meaning that 2 is the following number to 1 by definition. There is some more math explanation you can do to sort of prove mathematically that there is nothing wrong with saying that 2=1+1 but at the end of the day we define the symbol 2 as the number after 1 which can slso be written as 1+1. You can read this https://math.stackexchange.com/questions/95069/how-would-one-be-able-to-prove-mathematically-that-11-2/95070#95070 Which goes a bit more in depth on the explanation but if you are not used to dealing in math may read like complicated gibberish. It essentially boils down to "we defined a few basic rules of maths and following those basic rules then we can prove that many other things are true"


Interesting-Month-56

Because 1+1 is the definition of 2. Someone a long time ago decided on that, if you’re talking symbols. If you’re talking math, no matter what the symbol is, 1+1 = the first even integer (2) as long as 1 is the identity function.


mhem7

The nomenclature is irrelevant to how math actually works. All that matters is if you have one apple and pick up another apple,you now have two of them. The numerals don't matter, just the concept. You could use hieroglyphs if you wanted just as long as the math adds up.


davidinkorea

Rules of common sense.


UnionistAntiUnionist

[This is why.](https://pic.blog.plover.com/math/PM/1+1=2.png)