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I'm trying to find a single adjective that would fit the best to the following person's trait:
One who thinks knows everything/best, and often doesn't listen to orders and instead completes some task his/her own way. This person, while intelligent, is right about 50% of the time, when doing things its own way.
So far I've thought of independent, idiosyncratic and stubborn, but these words don't imply the "knows everything/best" part of the trait.