Answer 1:
First of all, there is
no way to prove that a hypothesis is
correct. This is a widespread misunderstanding
which educators should probably spend more time
correcting.
Evidence (i.e., results of experiments or
tests) can provide
support for or refute a hypothesis, but
not definitively show correctness. While the
results of a particular test may be in line with a
hypothesis, repeated tests or a different test may
show that a hypothesis is wrong.
As in
this article, the hypothesis of all balls
in a can being white is supported (but not proven)
by pulling out one that is white, and is refuted
(shown to be wrong) by repeating the test and
getting a black ball.
That being said, there is evidence that crop
circles are
not of extraterrestrial origin. For
example, the creators of some of the first modern,
complex crop circles
admitted making them, and subsequent
circles are known to be copycats. Some simpler
crop circles (e.g. plain round circles) are quite
likely made by natural weather phenomena similar
to dust devils.
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