Parmenides, an ancient Greek philosopher, believed in the principle of monism. According to Parmenides, all things of the universe are ultimately based on the principle of being or existence (being is). He argued that existence is eternal, unchanging, indivisible, and continuous. Parmenides denied the existence of non-being or nothingness and regarded it as a concept filled with contradictions and logical inconsistencies. For him, everything that exists is a manifestation of being and is therefore real and permanent.
Parmenides, the pre-Socratic philosopher, believed in the principle of the "One" or the "Unity." According to Parmenides' philosophy, all things of the universe are fundamentally composed of this One, which is eternal, unchanging, and indivisible. Parmenides argued that the One is necessary and cannot be created or destroyed. He believed that true reality is eternal and unchanging, and that the perception of change and plurality in the world is illusory. Therefore, the principle of all things in the universe for Parmenides is the timeless and unchangeable One.
