1+1=3<br />
man+woman=baby

Good question<br />
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We don’t question much of anything we are told, that’s how come a lot of people have a lot of head-knowledge. It could be said that the teacher knows that 1 + 1 = 2 *only* because he was told by someone else. And the person who told the person before this was told, the person before that was told, the person before that was told (and so on and so on.)<br />
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It’s a very deep subject, actually. Epistemology is the study of knowledge; how we know what we know and how we *think* we know what we know. True knowledge lies in experience, in that we only ever truly know what we experience.<br />
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1 + 1 = 2 is true; put 2 £1 coins together and you can see it does, when you spend it you can also see that it does from experience. However, if you mix 2 different chemical compounds it equals 1, because the two are mixed and therefore become one. As a general, and obvious, rule of thumb the figures work … but there are many instances where it does not. I can only believe that it equals 2 when it actually does and from either experience or open logic/calculations which I am familiar with; other than that, I am taking somones word for it.<br />
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Well … you did ask :-p<br />
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~F~

:)) good explanation. you can be a goood student of Theory of Knowledge study.

If I take off my pants I can count up to twenty one

Because when I have one thing, and I add one more thing, i have two things. One and one is the same as one plus one.

This borders on silly since it is so obviously true BUT if you require proof, scroll down the following link till "Quotations" and you'll see an actual, rigorous mathematical proof which even I can't understand.<br />
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Cause it does...that's math for ya!

Why DO you believe. M'Kay?

Because I can count :0

I counted my fingers and i found out I have two hands, two ears, two eyes and only one nose.....therefore, two nose is equivalent to a gorilla