When people don't know how to change something, they often start searching for a way to justify failure, rather than thinking about how they could try doing something different to make it work.
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If we pretend that you can teach anyone anything, we'll find out where it's not (yet) true. But if we think that when someone isn't learning it means they can't be taught, no one will even try.
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If you take the attitude that anything is possible, you'll find that a lot of things that were previously thought impossible actually do become possible.

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