For another example of truth in coding, consider namespace pollution. An unnecessary global variable is not just an invitation to bugs; if it’s overexposed, it’

For another example of truth in coding, consider namespace pollution. An unnecessary global variable is not just an invitation to bugs; if it’s overexposed, it’s lying. Its scope should be reduced to match its importance. I think he is saying that you can't trust a global variable as it could be not what you think it is (and thus lying) because of it's scope.