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Topic: Is it possible that 3+4=8?
Replies: 21   Last Post: Jan 29, 2011 9:06 AM

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Craig Feinstein

Posts: 398
Registered: 12/13/04
Is it possible that 3+4=8?
Posted: Jan 23, 2011 2:47 PM
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Let's pretend that we live in a world where there are invisible pixies
running around messing everything up. Let's say you have 3 balls in
your left hand and 4 balls in your right hand. Whenever you combine
the balls together, one of these invisible pixies secretly throws in
another ball, so that whenever you count the balls, you come up with 8
balls. So in this pretend world, it is a known fact that 3+4=8. Anyone
who disputes this fact in our pretend world is considered either crazy
or stupid.

In our real world, it is a known fact that 3+4=7. But how can we be
sure that there are no invisible pixies running around taking balls
away from us causing us to think that 3+4=7 when really 3+4=8?

My point is that mathematics is considered a deductive science, in
which everything is absolutely certain. But how can mathematics prove
that the above scenario cannot be true?

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