“Being” or “being and beings” might be the meta-notion when philosophy and science were still sharing the same mind or minds in ancient Greek and Europe. To find its meaning and to become a part of the meaning are however more and more vital nowadays, not for philosophy but for science, especially for physics and biology. The author proposes in this essay that this concept may mean to us nothing more or less than the unity or unification of Parmenides’ idea (...) “being is one” and Heraclitus’ idea “all things are in flux and nothing may remain the same”. That is just as to say that a being and an entity may never be identified with the same boundary. In other words, nothing or none should ever be understood as a being. This understanding is conceptualized and linguisticalized by the author as the compound symbol “OC”. And the OC represents a synthetic and also analytical understanding of both our universe and us together. And its value and strength may be found more obvious in his concise discussion, in the last part of the essay, on the OC’s meanings to ontology, epistemology, axiology, logic, mathematics, physics, biology, cosmogony and more. (shrink)