What is Materialism?
'''Materialism''' is the [[Philosophy|philosophical]] belief that the [[world]] is made of [[material]], and that there are no other types of [[wikt:entity|entity]] (things). Everything is composed of material. Things that are not made of material, such as [[consciousness]], are the result of actions by material.<ref>A materialist would say that 'consciousness is an '''epiphenomenon''' of the brain'.</ref> In other words, matter is the only real substance. ''[[Physicalism]]'' is a related term.<ref>Lange, Friedrich A. 1925. ''The history of materialism''. New York, Harcourt, Brace.</ref><ref>[http://plato.stanford.edu/entries/materialism-eliminative Eliminative materialism]</ref> Especially, a materialist does not believe in [[supernatural]] entities. Many of history's materialists thinkers have found the idea of a [[spirit]] either meaningless or not scientifically proven. By definition, these thinkers are therefore also [[atheists]], though not all atheists are materialists, and there have even been some historically important Materialist thinkers who believe in a [[Pantheism|Pantheist]] idea of [[God]] (such as [[Baruch Spinoza]] and [[Friedrich Engels]]). Modern philosophical materialists extend the definition to include other basic entities proven by [[science]], such as [[energy]], [[Force (physics)|forces]], and the curvature of [[Space (physics)|space]]. Matter and energy are known to be interchangeable, and much else, such as [[gravity]], is caused by matter. However, the concept of matter is itself not entirely clear.<ref>Vitzthum, Richard C. 1995. ''[https://books.google.com/books/about/Materialism.html?id=odjWAAAAMAAJ Materialism: an affirmative history and definition]''. Amherst, New York: Prometheus Books. </ref> There are other types of materialism that of philosophers have shared. Some examples are [[reductionism]], [[logical positivism]] and [[empiricism]]. The origin of materialism is in a type of [[Ancient Greek philosophy]]. [[Thales]], [[Epicurus]], and [[Lucretius]] are early materialis