The planet where human beings live together is facing great challenges. Sustainable agriculture and fisheries are the basis for human survival, which is currently facing threats from many sources, including increasing climate change, marine crisis and sharp decline in biodiversity; A large number of people will be forced to leave their homes due to climate change; Many fast-growing cities lack clean water resources; The threat of new epidemics is also unprecedented. Today's world is closely linked. These are the common problems faced by mankind. COVID-19's global rampage has shown that countries are interrelated, and what happens in every country affects other countries. The world is in danger and no country can be spared. To understand this vital fact, "taking the world as our own responsibility" (the "world system" proposed by Zhao TingYang, a researcher at the Institute of philosophy of the Chinese Academy of Social Sciences) is our direction. We must transcend different traditions, languages and political systems and work together on the basis of dialogue among civilizations. Cooperation based on mutual respect is based on "harmony but difference", rather than expecting others to be the same as themselves. No country or any way of thinking has answers that can solve all problems. We have two ways of "cooperation": one is the international geopolitical order; The other is scientific and technological cooperation and sharing. In the past two decades, scientific research cooperation between colleges and universities and academic research institutions has become increasingly close. One of every four scientific and technological papers is completed by international cooperation. The opening and sharing of data resources has greatly accelerated the research and development of new crown vaccine and saved millions of lives. China has made great contributions to the treasure house of human knowledge. The European Union, North America and China constitute the three major regions of world science. In terms of the total number of highly cited scientists in the comprehensive fields of mathematics, computer, engineering, materials and physics, Tsinghua University is in a leading position in the world, even higher than the Massachusetts Institute of technology. In 2018, Chinese and American scientists co authored 55382 papers, the two countries with the largest number of CO authored papers. In addition, Chinese scientists have also carried out extensive cooperation with their counterparts in Europe, other English speaking countries and Asia. Unfortunately, scientific and technical cooperation is being affected by the geopolitical situation. There are signs that the "new cold war" is on the rise - although few people who have experienced the "cold war" want to return to that painful, biased and divided world. How can we solve the climate, habitat, food, water and health crises by pouring resources into fossil fuel powered military confrontation? The fate of mankind shares weal and woe! Until recently, Europe and the United States have strongly supported exchanges with China. But now, researchers in western countries are facing the pressure of "decoupling" from China to varying degrees. The scientific research environment is full of doubt and self-examination. National interests are inevitable in the field of science and technology, and some data will not be shared. But this should be the exception, not the norm. If we give up communication out of unnecessary security concerns or false sense of superiority, it will bring disastrous consequences. In the face of geopolitical tensions, it is crucial that China and Western countries maintain as full scientific cooperation as possible on the basis of mutual respect, careful negotiation and agreement of rules and agreements and sustained trust. There will inevitably be some differences in policies and methods. When we "take the world as our own responsibility", we will gain something from the discussion of these differences. With goodwill, we can find solutions that meet each other's concerns, and all mankind will benefit from it. (outlook new era)