"Abbott, Edwin A - Flatland" - читать интересную книгу автора (Abbott Edwin A)

sight.
If however the Reader will take the trouble to refer to the
passage in which Recognition by Feeling is stated to be universal, he
will find this qualification -- "among the lower classes." It is only
among the higher classes and in our more temperate climates that Sight
Recognition is practised.
That this power exists in any regions and for any classes is the
result of Fog; which prevails during the greater part of the year in
all parts save the torrid zones. That which is with you in Spaceland
an unmixed evil, blotting out the landscape, depressing the spirits,
and enfeebling the health, is by us recognized as a blessing scarcely
inferior to air itself, and as the Nurse of arts and Parent os
sciences. But let me explain my meaning, without further eulogies on
this beneficent Element.
If Fog were non-existent, all lines would appear equally and
indistinguishably clear; and this is actually the case in those
unhappy countries in which the atmosphere is perfectly dry and
transparent. But wherever there is a rich supply of Fog, objects that
are at a distance, say of three feet, are appreciably dimmer than
those at the distance of two feet eleven inches; and the result is
that by careful and constant experimental observation of comparative
dimness and constant experimental observation of comparative dimness
and clearness, we are enabled to infer with great exactness the
configuration of the object observed.
An instace will do more than a volume of generalities to make my
meaning clear.
Suppose I see two individuals approaching whose rank I wish to
ascertain. They are, we will suppose, a Merchant and a Physician, or
in other words, an Equilaterial Triangle and a Pentagon; how am I to
distinuish them?
It will be obvious, to every child in Spaceland who has touched
the threshold of Geometrical Studies, that, if I can bring my eye so
that its glance may bisect an angle (A) of the approaching stranger,
my view will lie as it were evenly between the two sides that are next
to me (viz. CA and AB), so that I shall contemplate the two
impartially, and both will appear of the same size.
Now inthe case of (1) the Merchant, what shall I see? I shall see
a straight line DAE, in which the middle point (A) will be very bright
because it is nearest to me; but on either side the line will shade
away _rapidly to dimness,_ because the sides AC and AB _recede rapidly
into the fog_ and what appear to me as the Merchant's extremities,
viz. D and E, will be _very dim indeed._
On the other hand in the case of (2) the Physician, though I shall
here also see a line (D'A'E') with a bright centre (A'), yet it will
shade away _less rapidly_ to dimness, because the sides (A'C', A'B')
_recede less rapidly into the fog:_ and what appear to me the
Physician's extremities, viz. D' and E', will not be _not so dim_ as
the extremities of the Merchant.
The Reader will probably understand from these two instances how -
- after a very long training supplemented by constant experience -- it