Since a politician never believes what he says, he is surprised when others believe him
由于政客自己都不相信自己的话，因此要是有人相信他，他自己才觉得奇怪呢
Politicians have a reputation of being liars, a fact that prompted Charles de Gaulle to say,
政客说谎者著称,这一事实促使戴高乐说
"Since a politician never believes what he says, he is surprised when others believe him "
由于政客自己都不相信自己的话，因此要是有人相信他，他自己才觉得奇怪呢！
Even a politician doesn ’t believe what he himself says.
甚至政客不相信他自己说的话。