Most of all we should thank those who tried to do things that "cannot
be done". Most of them failed. Many of them died. But if they had
not tried...
I believe it was Heinlein who said something on the order of:
"If an elderly and knowledgeable scientist tells you something can be
done, he is very probably right. If an elderly and knowledgeable
scientist tells you something cannot be done, he is almost certainly
wrong."
To which I add:
Listen very carefully to WHY it cannot be done, because there's a
good chance he'll accidentally tell you how to do it.
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