There is no clear answer to this question because choosing Peking University or Tsinghua University as a scientist's degree is not the only deciding factor. Peking University and Tsinghua University were both top institutions of higher education in China with a high academic reputation and research strength. Both universities had excellent faculty and facilities to provide a wide range of science courses and research fields. The factors to consider when choosing a university may include: 1. Discipline: Choose a university that is related to the subject you are interested in because it will help you build in-depth professional knowledge and experience that will help you succeed in future scientific research. 2. Research strength and reputation: Consider the research strength and reputation of the university. The reputation and ranking of these universities in the relevant fields may affect their research opportunities and resources. 3. Faculty: Understand whether the university's faculty and mentors have rich experience and knowledge that matches their research interests. 4. Student community: Find out if the university's student community has an academic community that supports and motivates you. These communities can provide resources and opportunities to help you establish academic connections and carry out research projects. Therefore, choosing Peking University or Tsinghua University as a scientist was not the only deciding factor. One had to consider the above factors and make a choice based on one's own situation and preferences.