INTRODUCTION
sight, you could see all sides. Upon which it was suggested that
consequently you could not walk around a man who had been shut
up in a box ! And so on. The whole thing is amusingly stupid,
and if at the start you, very properly, decline to admit any
but a simple and correct definition of "to go around" there
is no puzzle left, and you prevent an idle, and often heated,
argument.
When you have grasped your conditions always see if you cannot
simplify them, for a lot of confusion is got rid of in this way. Many
people are puzzled over the old question of the man who, while
pointing at a portrait, says, " Brothers and sisters have I none, but
that man's father is my father's son." What relation did the man
in the picture bear to the speaker ? Here you simplify by saying
that " my father's son " must be either " myself" or
N
" my brother."
But, since the speaker has no brother, it is clearly " myself." The
statement simplified is thus nothing more than, " That man's father
is myself," and it was obviously his son's portrait. Yet people fight
over this question by the hour !
There are mysteries that have never been solved in many
branches of Puzzledom. Let us consider a few in the world of
numbers—little things the conditions of which a child can understand,
though the greatest minds cannot master. Everybody has heard the
remark, "It is as hard as squaring a circle," though many people
have a very hazy notion of what it means. If you have a circle of
given diameter and wish to find the side of a square that shall contain
exactly the same area, you are confronted with the problem of
squaring the circle. Well, it cannot be done with exactitude (though
we can get an answer near enough for all practical purposes) because
it is not possible to say in exact numbers what is the ratio of the
diameter to the circumference. But it is only in recent times that it
has been proved to be impossible, for it is one thing not to be able
to perform a certain feat, but quite another to prove that it cannot be
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