It is said in the Doctrine of the Mean, written by the grandson of Confucius, that the greatest knowledge, including both scientific concepts and human realizations, comes only from the everyday lives with an empty mind. The title of the book, Doctrine of the Mean, does not mean the middle way of the two extremes but the emptiness of the mind in everyday life. We call it as Moderation. This teaching of the Doctrine of the Mean connects its essence to Zarathustra by Nietzsche, as Heidegger explains in his book, What is Thinking. They all stressed that we cannot think without emptying our minds in the everyday lives. If one can think, one can do everything: Confucius' grandson called it a scholar or scientist, while Nietzsche called it Zarathustra.
After crossing the river with a raft, we have to abandon the raft to climb the mountain. Existing knowledge helps but guides us too much that it hinders us from obtaining newly formed representations to become the new corresponding concepts. When we look at a red flower, we may remind ourselves of the refraction of the color rather than think about the role of the color red for the flower to survive in nature. When we find a natural phenomenon with microorganisms, we may rely on genetic information, such as functional genes, rather than stick to the phenomenon as it is. However, when we observe an object or experience an event, we have the capability to create the subsequent representation which brings a new knowledge only when our mind is empty.
How to empty the mind filled with knowledge? The discourses of Confucius advise the two ways. Firstly, we can empty our mind by empathizing into the object (either nature or human) that we observe. When we meet a person who suffers, we may bring our mind into the mind of the suffering person, which is called empathy, instead of reminding ourselves of a social welfare system or related knowledge. When we visit and observe a river polluted with algae, we may bring the knowledge of eutrophication with nitrogen and phosphorus to explain it. Ironically, however, it is not easy to go beyond the thoughts of a scientist with this knowledge. Only when we bring ourselves into the polluted river, we may have a way to obtain new knowledge over the existing ones.
Secondly, we can empty our mind by thinking about justice whenever we have a chance to benefit ourselves, which surely applies to the scientist. We may understand this with the issues of climate change. Confucius asks us whether we want to solve emergent problems of climate change or take benefits from those. Confucius mentions that the consequences of empathy and act of justice, with an event, can become knowledge. But, we have to know the knowledge is ephemeral as it occurs only regarding the event. That is why Confucius never defines any knowledge but only tells examples from which we can understand the related knowledge.