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Counting in a different way
(why most of the time .5 is anything but between 0 and 1)
Counting in a different way? What does
it mean? That 2 and 2 would not make 4?
Yes they do, but 2 + .1 will not make 2.1 every time. For we will
have to reconsider the relation between whole numbers and their decimal
digits.

Then we go.
Cantor's absurd infinities
Ask a particles physicist about the
infinitesimal, he will tell you how very strange things happen there, which
are unthinkable at our scale. Such as that a particle can be a welllocated
corpuscle, and a wave of infinite size endlessly expanding in space, both
at the same time.
Ask a mathematician about the infinitely
great, he will tell you the same thing: when they reach infinity, numbers
gain properties which are unthinkable just before infinity.
For example, count the even wholenumbers
: 2, 4, 6, 8, etc.
You can easily calculate that whatever the moment you stop counting, their number will be half the total number of the whole numbers you have seen. Because, for every even number, you have to add one uneven number to have the total number of whole numbers. And you can see clearly, that this will continue, even if you count very far toward infinity: an even number, an uneven number, etc. That's a perfect and very simple alternation you can follow toward infinity. But when you are right at infinity, and count the infinite number of whole numbers you have encountered, and the number of even numbers you have picked up one time every two whole numbers, then you find that these numbers are not double and half one of the other: they are perfectly and strictly equal. 
Thus,
strange things happen at infinity, since a property true ... until infinity,
suddenly might be totally untrue when arriving right at infinity.
Of course, mathematicians are reasonable
people. If
they have to acknowledge such an insane fact, that's because it has been
proved. It's the logical conclusion of a demonstration, and a mathematician
cannot elude a logical conclusion.

It begins with a trick to compare
all the sets, without needing to count all their elements. This enables
us to compare even the infinite sets we cannot count.
The trick is to pair the two sets,
by associating each element of one of the sets with one element of the
other set. And we see whether anything remains in the second when the first
is exhausted. Of course, in the case of infinite sets, we do not really
make the pairing for all the elements. But we find a method used as principle,
and we wonder if anything would remain by applying this method.
For
example, to compare the infinite number of whole numbers, and the infinite
number or irrational numbers, the method is as follows:
1/
we begin by supposing that we draw up an exhaustive list with all irrational
numbers, and we put them all in a vertical column.
[We recall that irrational numbers are numbers which have an infinite number of decimal digits. In that infinite series, no periodicity can be found to imagine next digits by studying previous digits. 'Pi' for instance, is an irrational number] 
The
answer is yes.
To find an irrational number which
is not paired with a whole number, we only have to pick up the 1st irrational
number in the list and change its 1st digit, then to change its 2nd digit
in order to make it different from the 2nd digit of the 2nd irrational
number of the list, then to change its 3rd digit to make it different,
etc.
When we have reached the last irrational
number paired with a whole number just at infinity, we have then formed
a new irrational number. That new one is different from all those which
are paired for it is different from every of them by one digit at least.
Thus, the column of irrationals,
holds at least one number which is not paired with a whole number. Therefore,
irrational numbers are more numerous than the infinite number of whole
numbers.
Probably, the
comparison between whole numbers and irrational numbers, does not have
many practical consequences for itself. But with the same processes, Cantor
demonstrated 'more serious' things. Serious, that is if we try to use numbers
to represent physical phenomena, and in particular to define space properties.
Thus, we can demonstrate that there are more points in a tiny segment of a straight line than there are numbers in the infinite set of whole numbers. 'Worse', we can demonstrate that every segment of a straight line, whatever its size, holds the same number of points. And that there are as many points in a straight line 1 D, than in a 2 D plane, and even than in a 3 D volume. In short, all the commonsense properties about the relation of space dimensions, which are likely to prolong themselves continuously and regularly until infinity, would be invalidated all in a sudden, precisely after infinity. Properties usually incompatible with each other, would turn to be so, when at infinity. 
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