Nothing, no-thing, or no thing is when there is not anything. It is the opposite of something. It is also an antithesis (complete opposite) of everything. The idea of nothing has been debated in philosophy since the 5th century BCE. Early Greek philosophers said it was impossible for nothing to "exist". The atomists said there could be nothing, but only between the spaces between atoms. For them, however, all space was filled with atoms. Aristotle thought that there is matter and there is space. He said that space is an object that matter can be placed in. This became the norm for modern scientist, like Isaac Newton. However, some philosophers, like René Descartes, still argued that there was no empty space. These arguments continued until the discovery of a physical vacuum.
Existentialists like Jean-Paul Sartre and Martin Heidegger make a connection between nothing and consciousness. Some writers have made connections between Heidegger's idea of nothing and the nirvana of Eastern religions.
Modern science does not say a vacuum is nothing. In quantum field theory, a vacuum has many virtual particles. The quantum vacuum can be called a modern aether theory.
