Sein

Philosophers often suppose a certain sense of being as primary, and from it derive other senses of being as secondary. So, even if they use the same word "is," the meaning of being is different, depending upon what it is that "is": sensible material beings, values and norms, principles, mathematical objects, quality, time , space , God , etc. For Plato the primary kind of being is the immutable world of ideas , while for Aristotle it is the mutable world of substances . In another context, however, Aristotle put one immutable substance, God, as the principle of all being, and Thomas Aquinas , too, conceived God as the primary being, from which all other beings in the world receive their existence. Materialists conceive material or a sensible entity as the primary model of being, while idealists regard thought or spirit as primary. Most philosophers, including Aristotle, Edmund Husserl and Martin Heidegger , were aware of these diverse senses of being. Inquiries into being often contrast it with its reciprocal concept, and the meaning of being varies accordingly. Paired sets include: being and becoming, being and non-being, being and appearance or phenomena, being and existence , being and essence , being and beings, being and thought, and being and ought. How to approach the question of being is determined by the style of thought, philosophical approach, or methodology. For example, the phenomenological approaches of Husserl and Heidegger locate the question of being on the horizon of human consciousness and existence. Eastern philosophies emphasize the role of "non-being" for our understanding of being. Many philosophical and religious traditions seem to agree that elucidating the nature of being discloses a fundamental distinction between an essential world and a resultant world of phenomena. They also seem to agree that each of the two worlds has diversity within itself with some kind of purposiveness. Yet they give different answers to the question of which of the two worlds is more real. The pre-Socratic Greeks had a more direct, non-conceptual, and non-objectifying approach to the question of "being," as compared with the rather indirect approach of Plato and Aristotle that attempted to conceptualize and objectify "being" through instantiated forms or formed matter. For the pre-Socratics, the most important question to be answered was: What is the world made of? In answering this question, they were immediately convinced that all things in the world are identical in nature with one another. Hence, they successively attempted to reduce the world in general to water (Thales ), then to air (Anaximenes ), then to fire (Heraclitus ), until Parmenides finally said that the whole world is made of "being" ( to on, the present participle of the verb einai, "to be.") Parmenides' answer was more persuasive because while it was not at once evident that water, air, and fire are completely identical, it was undeniable that they all have in common the property of being, because they all are . Being, then, was considered to be the fundamental and ultimate element of all that is. Usually contrasted with Parmenides' notion of being as the ultimate principle that is immutable and eternal, is Heraclitus ' understanding of fire as the ultimate element of reality, according to which the whole of reality is mutable and transitory like fire. For Heraclitus, everything is in flux and becoming, and immutability or stability is illusory. Perhaps the only sense in which he was able to talk about true being was this unchanging principle of transitory passage and its cyclicality. Plato differentiated between the immutable world of ideas or forms and the transitory world, saying that the former is an eternal, incorporeal realm of ideas and values that are true beings, while the latter is a less real, ephemeral, "shadowy" world of material things that are far from true beings and subject to change and decay. This way, Plato struck a compromise b