idea or belief that only natural laws and forces operate in the universe
In philosophy, naturalism is the idea or belief that only natural laws and forces (as opposed to supernatural or spiritual ones) operate in the universe. Adherents of naturalism assert that natural laws are the only rules that govern the structure and behavior of the natural world, and that the changing universe is at every stage a product of these laws.
Naturalism is not so much a special system as a point of view or tendency common to a number of philosophical and religious systems; not so much a well-defined set of positive and negative doctrines as an attitude or spirit pervading and influencing many doctrines. As the name implies, this tendency consists essentially in looking upon nature as the one original and fundamental source of all that exists, and in attempting to explain everything in terms of nature. Either the limits of nature are also the limits of existing reality, or at least the first cause, if its existence is found necessary, has nothing to do with the working of natural agencies. All events, therefore, find their adequate explanation within nature itself. But, as the terms nature and natural are themselves used in more than one sense, the term naturalism is also far from having one fixed meaning.
According to philosopher David Papineau, naturalism can be separated into an ontological sense and a methodological sense. "Ontological" refers to ontology, the philosophical study of what exists. On an ontological level, philosophers often treat naturalism as equivalent to materialism. For example, philosopher Paul Kurtz argues that nature is best accounted for by reference to material principles. These principles include mass, energy, and other physical and chemical properties accepted by the scientific community. Further, this sense of naturalism holds that spirits, deities, and ghosts are not real and that there is no "purpose" in nature. This stronger formulation of naturalism is commonly referred to as metaphysical naturalism. On the other hand, the more moderate view that naturalism should be assumed in one's working methods as the current paradigm, without any further consideration of whether naturalism is true in the robust metaphysical sense, is called methodological naturalism.With the exception of pantheists—who believe that Nature is identical with divinity while not recognizing a distinct personal anthropomorphic god—theists challenge the idea that nature contains all of reality. According to some theists, natural laws may be viewed as secondary causes of God(s).
In the 20th century, Willard Van Orman Quine, George Santayana, and other philosophers argued that the success of naturalism in science meant that scientific methods should also be used in philosophy. According to this view, science and philosophy are not always distinct from one another, but instead form a continuum.
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