Из Understanding Arguments.

Trick of the disappearing guard - Perhaps the secretary of state has not been candid with the Congress. Of course, he has a right to his own views, but this is a democracy where officials are accountable to Congress. It is time for him to level with us. The force of the guarding term “perhaps” that begins this passage disappears at the end, where it is taken for granted that the secretary of state has not been candid.

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