Natural philosophy or the
philosophy of nature (from
Latin philosophia naturalis), is a term applied to the
objective study of
nature and the physical
universe that was dominant before the development of
modern science. It is considered to be the precursor of
natural sciences such as
physics.
Forms of science historically developed out of philosophy or more specifically natural philosophy. At older universities, long-established Chairs of Natural Philosophy are nowadays occupied mainly by physics professors. Modern notions of science and scientists date only to the 19th century (Webster's Ninth New Collegiate Dictionary dates the origin of the word "scientist" to 1834). Before then, the word "science" simply meant knowledge and the label of scientist did not exist. Isaac Newton's 1687 scientific treatise is known as The Mathematical Principles of Natural Philosophy.
In the 18th and 19th centuries, natural philosophy referred to what is now called physical science. From the mid-19th century, when it became increasingly unusual for scientists to contribute to both physics and chemistry, it just meant physics, and is still used in that sense in degree titles at the University of Oxford. Natural philosophy was distinguished from the other pre-cursor of modern science, natural history, in that the former involved reasoning and explanations about nature (and after Galileo, quantitative reasoning), whereas the latter was essentially qualitative and descriptive.
In what is thought to be one of Plato's earliest dialogues, Charmides, the distinction is drawn between sciences or bodies of knowledge which produce a physical result, and those which do not. Natural philosophy has been categorized as a theoretical rather than a practical branch of philosophy (like ethics). Sciences that guide arts and which draw upon the philosophical knowledge of nature can of course produce many practical results, but these subsidiary sciences (e.g. architecture or medicine) are considered to go beyond natural philosophy.
