Limiting beliefs, such as 'I'm not smart enough' or 'I'm not good at math, ' can keep people from attempting more complex challenges.

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Professor NOGUERA: Well I'm a man of faith too, but I think relying on prayer is probably not good enough here.

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As far as I'm concerned, however, that's not good enough.

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"I'm not sure whether the technology they've got there is good enough as far as frames per second, " said Greatbatch after an inconclusive replay saw the umpires again rule in the tourists' favour.

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Although it would definitely be useful to know your car's fuel mileage (a decline in miles per gallon is a good indicator of potential problems), I'm not dedicated enough to enter every single gasoline purchase.

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