Premise: Xi Jinping . As General Secretary , Xi holds an ex-officio seat on the Politburo Standing Committee , China 's top decision-making body . Xi joined the Politburo Standing Committee and central secretariat in October 2007 , spending the next five years as Hu Jintao 's presumed successor .
Hypothesis: Xi Jinping did not join the Politburo Standing Committee.
Label: CONTRADICTION