Nothing

Nothing is a concept denoting the absence of something, and is associated with nothingness. In nontechnical uses, nothing denotes things lacking importance, interest, value, relevance, or significance.Nothingness is the state of being nothing, the state of nonexistence of anything, or the property of having nothing.

Some would consider the study of "nothing" to be foolish. A typical response of this type is voiced by Giacomo Casanova (1725–1798) in conversation with his landlord, one Dr. Gozzi, who also happens to be a priest:

However, "nothingness" has been treated as a serious subject for a very long time. In philosophy, to avoid linguistic traps over the meaning of "nothing", a phrase such as not-being is often employed to make clear what is being discussed.

One of the earliest western philosophers to consider nothing as a concept was Parmenides (5th century BC), who was a Greek philosopher of the monist school. He argued that "nothing" cannot exist by the following line of reasoning: To speak of a thing, one has to speak of a thing that exists. Since we can speak of a thing in the past, this thing must still exist (in some sense) now, and from this he concludes that there is no such thing as change. As a corollary, there can be no such things as coming-into-being, passing-out-of-being, or not-being.

Parmenides was taken seriously by other philosophers, influencing, for instance, Socrates and Plato. Aristotle gives Parmenides serious consideration but concludes; "Although these opinions seem to follow logically in a dialectical discussion, yet to believe them seems next door to madness when one considers the facts."

Leucippus (early 5th century BC), one of the atomists, along with other philosophers of his time, made attempts to reconcile this monism with the everyday observation of motion and change. He accepted the monist position that there could be no motion without a void. The void is the opposite of being. It is not-being. On the other hand, there exists something known as an absolute , a space filled with matter, and there can be no motion in a plenum because it is completely full. But, there is not just one monolithic plenum, for existence consists of a multiplicity of plenums. These are the invisibly small "atoms" of Greek atomist theory, later expanded by Democritus (circa 460 BC – 370 BC), which allows the void to "exist" between them. In this scenario, macroscopic objects can come-into-being, move through space, and pass into not-being by means of the coming together and moving apart of their constituent atoms. The void must exist to allow this to happen, or else the "frozen world" of Parmenides must be accepted.

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