Re: Have the Q ever told an untruth?
He told Janeway that the Q have never reproduced, directly contradicting the Next Gen episode "True Q" - but that wasn't an in-universe lie, it was the writers pretending the prior episode never happened.
As for a real fib told in-universe, I'm not sure.
The Q in question in True Q of course left the continuum and became human when they reporduced, so technically that wasn't a lie, just the truth from a certain point of view.
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